LPCN: Lipocine Inc Analysis and Research Report
2018-04-23 - by Asif , Contributing Analyst - 147 views
Lipocine is a specialty pharmaceutical company focused on applying its oral drug delivery technology for the development of pharmaceutical products in the area of men’s and women’s health. The company's proprietary delivery technologies are designed to improve patient compliance and safety through orally available treatment options. The company's primary development programs are based on oral delivery solutions for poorly bioavailable drugs. Lipocine has a portfolio of proprietary product candidates designed to produce favorable pharmacokinetic (“PK”) characteristics and facilitate lower dosing requirements, bypass first-pass metabolism in certain cases, reduce side effects, and eliminate gastrointestinal interactions that limit bioavailability. The company's lead product candidate, TLANDO™, is an oral testosterone replacement therapy (“TRT”) and is currently under review by the United States Food and Drug Administration (“FDA”) with a Prescription Drug User Fee Act (“PDUFA”) action goal date of May 8, 2018. The FDA has deemed the resubmission a complete response to its June 2016 Complete Response Letter (“CRL”) that requested additional information related to the dosing algorithm for the proposed label. The TLANDO New Drug Application (“NDA”) is based on the results of the Dosing Validation (“DV”) study. The DV study confirmed the efficacy of TLANDO with a fixed dose regimen without need for dose adjustment. TLANDO was well tolerated upon 52-week exposure with no reports of drug related Serious Adverse Events (“SAEs”). On January 10, 2018, the Bone, Reproductive and Urologic Drugs Advisory Committee (“BRUDAC”) of the FDA voted six in favor and thirteen against the acceptability of the overall benefit/risk profile to support approval of TLANDO as a TRT. The company continue to work with the FDA in addressing topics discussed by BRUDAC. The company may receive another CRL. This would cause delays and added expense to the process of seeking approval of TLANDO. Additional pipeline candidates include LPCN 1111, a next generation oral testosterone therapy product with the potential for once daily dosing, that is currently in Phase 2 testing, and LPCN 1107, which has the potential to become the first oral hydroxyprogesterone caproate product indicated for the prevention of recurrent preterm birth and has completed an End-of-Phase 2 meeting with the FDA.
Testosterone, or T, is the primary circulating sex hormone in males and is critical to the development and maturation of reproductive tissues as well as other secondary male characteristics such as muscle growth and bone density. Synthesized in the gonads of both males (testis) and females (ovaries), testosterone circulates bound to sex hormone binding globulin (“SHBG”, ~60%), loosely bound to albumin, a protein in the blood that binds to testosterone (~40%), or as a free molecule (~1%). Once circulating, testosterone enters cells directly and activates a network of proteins that ultimately result in metabolic conversions, which in turn produce observable effects. The concentration of circulating testosterone can vary drastically over time or between individuals and can be dependent on genetic factors, other medical conditions, lifestyle behaviors, and/or concurrent medication administration. Although large variability exists, the effects of testosterone are also determined by a number of factors including the amount of steroid penetration, sensitivity of enzymes and cellular proteins to the hormone, and the action of genomic receptors at the cellular level. As a result, assessing clinically low, or potentially high, levels of naturally occurring testosterone often requires a number of quantitative tests in conjunction with clinical evaluations.
Low serum testosterone causes significant clinical impact and can result in erectile dysfunction, low libido, decreased muscle mass and strength, increased body fat, decreased bone density, decreased vitality and depressed mood. Furthermore, low serum testosterone concentrations have been found to be an independent predictor of a number of cardiovascular risk factors including obesity, abnormal lipid levels, hypertension, type 2 diabetes, and systemic inflammation. Well-designed, prospective clinical trials have determined that low testosterone levels are also independently associated with mortality risk. These findings have generated interest amongst the medical community and general public regarding the importance of maintaining appropriate serum testosterone levels, which has stimulated growth of the testosterone replacement therapy market which peaked in 2013. The testosterone therapy market has contracted modestly since 2013 due to a number of factors including the withdrawal of direct to consumer advertising mid-2014.
Hypogonadism typically refers to a permanent deficiency of sex hormones rather than a temporary deficiency that may be related to acute/chronic illnesses or other medical, personal, or environmental factors. Primary hypogonadism describes disease states that intrinsically affect the gonads. Examples of these include the genetic disorders, Turner syndrome and Kleinfelter syndrome. Secondary hypogonadism refers to disease states that affect gonadal-related structures such as the hypothalamus and pituitary gland that directly impact the development of gonads and as such the release of testosterone and other sexual hormones. Kallmann syndrome, in which patients fail to undergo all of the changes associated with puberty, is a type of secondary hypogonadism. Although a number of inherited diseases are known to affect the gonads either directly or indirectly, it is generally believed that the majority of individuals with hypogonadism develop the condition as a result of age-related declines in testosterone or other acquired conditions.
Diagnosis and Treatment of Hypogonadism
Epidemiological studies have determined that total testosterone follows an age-related decline with mean serum concentration at the age of 75 years approximately two thirds that at 25 years. Because naturally occurring testosterone exists at low concentrations, with normal testosterone levels in the range of 300 to 1080 ng/dL automated platform-based assays have been found to lack specificity and are prone to inter-lab variability. The lack of reliable laboratory tests is complicated further by the inter-individual variability seen in an unaffected population. Thus, in order to accurately diagnose hypogonadism in a male, at least two morning serum testosterone levels are performed in conjunction with a clinical assessment of patient symptoms. Patients can only be diagnosed when they present with symptoms that are directly related to low morning serum testosterone level.
Treatment for male hypogonadism (both primary and secondary) is testosterone replacement therapy, or TRT. Some of the reported benefits of TRT include improved libido and sexual function; increased bone density, muscle development, and cognition; as well as a reduction in other risk factors caused by low testosterone.
Testosterone Replacement Market
Due to the wide variability in therapeutic range and other medical conditions that may confound an accurate diagnosis, there is a consensus that male hypogonadism is significantly undertreated. A large study of 2,162 men over the age of 45 visiting primary care practices in the United States revealed that the prevalence of hypogonadism is about 39%. Based on this prevalence rate and the U.S. Census Bureau’s 2014 estimate that there are 45 million men between 45 and 75 years old, approximately 19 million men in the U.S. may have low testosterone. In the study, fewer than 4% of patients were receiving treatment for hypogonadism.
Testosterone replacement therapies have been commercially available in the United States for over 70 years and have followed a progression of delivery systems that included subcutaneous, or under-the-skin, intramuscular, transdermal patch, and finally topical gels, which initially surfaced in 2000, and creams. In 2014, a long acting intramuscular injection and an intranasal delivery system for testosterone were approved. The difficulty in creating an easy to use/administer and clinically effective testosterone therapy is related to the molecule’s complex pharmacokinetics. Pharmacokinetics, or PK, describe how the body affects a specific drug after administration through the mechanism of absorption and distribution, as well as the chemical changes of the substance in the body. For example, oral therapies, which would ideally be the most popular route of delivery, require multiple, high daily doses due to low bioavailability. Bioavailability is the fraction of a drug dose that is actually absorbed into the bloodstream. Additionally, the few oral therapies that have been used in the United States previously quickly went out of favor after significant side effects were revealed, most notably liver toxicity.
Currently, the U.S. TRT market consists of therapies that exist in four forms:
- intranasal; and
- buccal tablet, which is a tablet shaped patch applied to the upper gums.
Although transdermal patches were previously the most desirable application type, gel-based TRT has gained increasing popularity due to improved skin tolerability. Despite becoming a popular approach to male hypogonadism treatment, topical gels are not without limitations. Topical gels place women and children at risk of testosterone transference (secondary exposure to gels), which has prompted the FDA to add black box warnings relating to testosterone transference in the label of approved topical products. Despite these limitations, gels have continued to demonstrate significant market penetration.
The male testosterone market was $1.7 billion in 2017 according to IMS Health data. Additionally testosterone replacement prescriptions were approximately 7.0 million in 2017 according to IMS Health data. Injectables are the predominant dosage form in this market in terms of annual prescriptions written although topical gels garner the majority of the dollar sales and also have a significant share of total annual prescriptions. The historical growth in the market was driven by increasing recognition by both patients and providers of the prevalence of hypogonadism and its far-reaching medical consequences. Top treatments are marketed by AbbVie and Endo.
The company's current portfolio, shown below, includes its lead product candidate, TLANDO, an oral testosterone replacement therapy that is currently under review by the FDA with a PDUFA goal date of May 8, 2018. Additionally, Lipocine is in the process of establishing its pipeline of other clinical candidates including a next generation potential once daily oral testosterone replacement therapy, LPCN 1111, and an oral therapy for the prevention of preterm birth, LPCN 1107.
These products are based on its proprietary Lip’ral drug delivery technology platform. Lip’ral technology is a patented technology based on lipidic compositions which form an optimal dispersed phase in the gastrointestinal environment for improved absorption of insoluble drugs. The drug loaded dispersed phase presents the solubilized drug efficiently at the absorption site (gastrointestinal tract membrane) thus improving the absorption process and making the drug less dependent on physiological variables such as dilution, gastro-intestinal pH and food effects for absorption. Lip’ral based formulation enables improved solubilization and higher drug-loading capacity, which can lead to improved bioavailability, reduced dose, faster and more consistent absorption, reduced variability, reduced sensitivity to food effects, improved patient compliance, and targeted lymphatic delivery where appropriate.
TLANDO: An Oral Product Candidate for Testosterone Replacement Therapy
The company's lead product, TLANDO, is an oral formulation of the chemical, testosterone undecanoate (“TU”), an eleven carbon side chain attached to testosterone. TU is an ester prodrug of testosterone. An ester is chemically formed by bonding an acid and an alcohol. Upon the cleavage, or breaking, of the ester bond, testosterone is formed. TU has been approved for use outside the United States for many years for delivery via intra-muscular injection and in oral dosage form and recently TU has received regulatory approval in the United States for delivery via intra-muscular injection. Lipocine is using its proprietary technology to facilitate steady gastrointestinal solubilization and absorption of TU. Proof of concept was initially established in 2006, and subsequently TLANDO was licensed in 2009 to Solvay Pharmaceuticals, Inc. which was then acquired by Abbott Products, Inc. ("Abbott"). Following a portfolio review associated with the spin-off of AbbVie by Abbott in 2011, the rights to TLANDO were reacquired by it. All obligations under the prior license agreement have been completed except that Lipocine will owe Abbott a perpetual 1% royalty on net sales. Such royalties are limited to $1 million in the first two calendar years following product launch, after which period there is not a cap on royalties and no maximum aggregate amount. If generic versions of any such product are introduced, then royalties are reduced by 50%.
The company resubmitted its NDA to the FDA in August 2017 based on the results of the DV study. The DV study confirmed the efficacy of TLANDO with a fixed dose regimen without need for dose adjustment. TLANDO was well tolerated upon 52-week exposure with no reports of drug related Serious Adverse Events (“SAEs”). The FDA accepted its NDA as a complete response to their CRL and assigned a PDUFA goal date of May 8, 2018 for completion of the review. On January 10, 2018, the BRUDAC of the FDA voted six in favor and thirteen against the benefit/risk profile of TLANDO. Discussion topics during the BRUDAC included whether the safety of TLANDO is adequately characterized and whether additional data is need pre-approval or post approval, including the need for an ambulatory blood pressure (“ABPM”) study. Additional areas discussed included the potential to increase cardiovascular risk, lipid changes, hematocrit increase, levels of dihydro-testosterone and estradiol, cosynotropin stimulation results, Cmax excursions, the stopping criteria for use in clinical practice, and whether testosterone concentrations measured in serum tubes are reliable in patients treated with TLANDO. Particularly the FDA may be concerned with TLANDO’s potential for increased adverse cardiovascular outcomes in the population that will likely use the drug, if approved, and observed treatment emergent adverse reactions. The company continue to work with the FDA in addressing topics discussed by BRUDAC. The FDA may or may not view BRUDAC’s TLANDO advice/recommendation similarly. Lipocine has submitted two protocols to the FDA under its TLANDO investigational new drug (“IND”) application. The first protocol is for the conduct of an ABPM clinical study and the second protocol is for a phlebotomy clinical study to confirm no ex-vivo conversion of TU to T. The company plan to initiate both clinical studies ahead of its PDUFA date. Although there is no guarantee of FDA approval of TLANDO, the company believe the results from the DV study confirm the validity of a fixed dose approach without the need for dose titration to orally administering TLANDO. However, approval of its NDA on its PDUFA date is not guaranteed and the company may receive another CRL. Receipt of another CRL would result in substantial delays which may include additional studies and expense before the company would be in a position to re-submit an NDA responsive to such additional CRL.
Previously on June 28, 2016, the company received a CRL from the FDA on its original NDA submission. A CRL is a communication from the FDA that informs companies that an application cannot be approved in its present form. The CRL identified deficiencies related to the dosing algorithm for the label. Specifically, the proposed titration scheme for clinical practice was significantly different from the titration scheme used in the Phase 3 trial leading to discordance in titration decisions between the Phase 3 trial and real-world clinical practice. In response to the CRL, the company met with the FDA in a Post Action meeting and proposed a dosing regimen to the FDA based on analyses of existing data. The FDA noted that while the proposed dosing regimen might be acceptable, validation in a clinical trial would be needed prior to resubmission. The DV study was in response to the FDA’s request. The company also initiated the Dosing Flexibility (“DF”) study to assess TLANDO in hypogonadal males on a fixed daily dose of 450 mg divided into three equal doses.
Results from DV and DF Studies
The DV and DF studies were both an open-label, fixed dose (no titration), single treatment clinical study of oral TRT in hypogonadal males with low testosterone (T) (< 300 ng/dL) that assessed TLANDO in hypogonadal males on a fixed daily dose of 450 mg divided into two equal doses (“BID”) in the DV study and into three equal doses (“TID”) in the DF study. In total, 95 and 100 subjects were enrolled into DV and DF studies, respectively, with 94 and 98 subjects completing the DV and DF studies, respectively.
On June 19, 2017, the company announced top-line results of the DV and DF studies. Although there is no guarantee of FDA approval of TLANDO, the company believe the results from the DV study confirm the validity of a fixed dose approach without the need for dose titration to orally administering TLANDO. The DV study will be considered its pivotal efficacy clinical study for the NDA resubmission. TLANDO successfully met the FDA primary efficacy guidelines in the DV study safety statistical analysis set (“SS”) where 80% of the subjects achieved average testosterone levels (“Cavg”) within the normal range with a lower bound confidence interval (“CI”) of 72%. The DF study restored 70% of the subjects’ average testosterone levels within the normal range (Cavg) confirming that twice daily (“BID”) dosing is the appropriate dosing regimen for TLANDO and was the basis for resubmission. The safety set is defined as any subject that was randomized into the study and took at least one dose (N=95 subjects in the DV study and N=100 in the DF study). A baseline carried forward approach was used to account for missing data as a result of subject discontinuation.
The primary efficacy endpoint is the percentage of subjects with Cavg within the normal range, which is defined as 300-1080 ng/dL. The FDA guidelines for primary efficacy success is that at least 75% of the subjects on active treatment achieve a testosterone Cavg within the normal range; and the lower bound of the 95% CI must be greater than or equal to 65%.
The adverse event profile of TLANDO in both the DV and DF studies was consistent with the previously conducted 52-week Phase 3 Study of Androgen Replacement (“SOAR”) clinical trial. All drug related adverse events (“AEs”) were either mild or moderate in intensity and none were severe. To date, the safety database of TLANDO includes ~525 unique hypogonadal men demonstrating a profile consistent with other TRT products.
The secondary endpoints assessed the maximum total testosterone concentration (“Cmax”) post dosing using predetermined limits developed by the FDA for transdermals. The FDA guidelines for secondary efficacy success is that at least 85% of the subjects achieve Cmax less than 1500 ng/dL; no greater than 5% of the subjects have Cmax between 1800 ng/dl and 2500 ng/dL; and zero percent of the subjects have Cmax greater than 2500 ng/dL. Consistent with the definition of Cmax and the pharmacokinetic profile of multiple times a day dosing, two pre-specified analyses were performed, Cmax per dose and Cmax per day.
In the DV study SS Cmax per dose analysis, the percentage of subjects with Cmax less than 1500 ng/dL and between 1800 ng/dL and 2500 ng/dL were 85% and 7%, respectively. Deviations from the predetermined limits in the DV study were observed in the Cmax per day dose analysis for these thresholds. Only one subject, who was a major protocol violator, exceeded the 2500 ng/dL limit independent of per dose or per day dose analyses.
The DF study SS met all Cmax thresholds in per dose and per day dose analyses.
Prior to conducting the DV study and the DF study, the company completed its SOAR pivotal Phase 3 clinical study evaluating efficacy and 52-week safety of TLANDO. The SOAR study is considered its pivotal safety clinical study for the NDA resubmission.
Results from SOAR
SOAR was a randomized, open-label, parallel-group, active-controlled, Phase 3 clinical study of TLANDO in hypogonadal males with low testosterone (< 300 ng/dL). In total, 315 subjects at 40 active sites were assigned, such that 210 were randomized to TLANDO and 105 were randomized to the active control, AndroGel 1.62%®, for 52 weeks of treatment. The active control is included for safety assessment. TLANDO subjects were started at 225 mg TU (equivalent to ~ 142 mg of T) twice daily (“BID”) with a standard meal and then dose titrated, if needed, based on average T levels during the day, Cavg, and peak serumT levels, Cmax, up to 300 mg TU BID or down to 150 mg TU BID based on serum testosterone measured at weeks 3 and 7 based on PK profile with multiple blood samples drawn at each time period. The mean age of the subjects in the trial was ~53 years with ~91% of the patients < 65 years of age. The discontinuation rate for TLANDO was 38% compared 32% for AndroGel 1.62%®.
Primary statistical analysis was conducted using the Efficacy Population Set ("EPS"). The EPS is defined as subjects randomized into the study with at least one PK profile and no significant protocol deviations and includes imputed missing data by last observation carried forward, N=151. Further analysis was performed using the full analysis set ("FAS") (any subject randomized into the study with at least one post-baseline efficacy variable response, N=193) and the SS (any subject that was randomized into the study and took at least one dose, N=210).
**Safety ** The safety component of the SOAR trial was completed the last week of April 2015. The safety extension phase was designed to assess safety based on information such as metabolites, biomarkers, laboratory values, serious adverse events ("SAEs") and AEs, with subjects on their stable dose regimen in both the treatment arm and the active control arm. TLANDO treatment was well tolerated in that there were no hepatic, cardiac or drug related SAEs.
TLANDO safety highlights include:
- TLANDO was well tolerated during 52 weeks of dosing;
- Overall AE profile for TLANDO was comparable to the active control;
- Cardiac AE profiles were consistent between treatment groups and none of the observed cardiac AEs occurred in greater than 1.0% of the subjects in the TLANDO arm and none were classified as severe; and
- All observed adverse drug reactions (“ADRs”) were classified as mild or moderate in severity and no serious ADRs occurred during the 52-week treatment period.
Food Effect Study
The company also completed its labeling "food effect" study in May 2015. Results from the labeling "food effect" study indicate that bioavailability of testosterone from TLANDO is not affected by changes in meal fat content. The results demonstrate comparable testosterone levels between the standard fat meal (similar to the meal instruction provided in the Phase 3 clinical study) and both the low and high fat meals. The labeling “food effect” study was conducted per the FDA requirement and the company submitted preliminary results from this study to the FDA in the second quarter of 2015 prior to submitting the NDA.
Other Safety Requirements
Based on its meetings with the FDA, the company do not expect to be required to conduct a heart attack and stroke risk study or any additional safety studies prior to the potential approval of its NDA for TLANDO. The company may, however, be required to conduct a heart attack and stroke risk study on its own or with a consortium of sponsors that have an approved TRT product subsequent to the potential approval of TLANDO.
LPCN 1111: A Next-Generation Oral Product Candidate for TRT
LPCN 1111 is a next-generation, novel ester prodrug of testosterone which uses the Lip’ral technology to enhance solubility and improve systemic absorption. The company completed a Phase 2b dose finding study in hypogonadal men in the third quarter of 2016. The primary objectives of the Phase 2b clinical study were to determine the starting Phase 3 dose of LPCN 1111 along with safety and tolerability of LPCN 1111 and its metabolites following oral administration of single and multiple doses in hypogonadal men. The Phase 2b clinical trial was a randomized, open label, two-period, multi-dose PK study that enrolled hypogonadal males into five treatment groups. Each of the 12 subjects in a group received treatment for 14 days. Results of the Phase 2b study suggest that the primary objectives were met, including identifying the dose expected to be tested in a Phase 3 study. Good dose-response relationship was observed over the tested dose range in the Phase 2b study. Additionally, the target Phase 3 dose met primary and secondary end points. Overall, LPCN 1111 was well tolerated with no drug-related severe or serious adverse events reported in the Phase 2b study.
Additionally in October 2014, the company completed a Phase 2a proof-of-concept study in hypogonadal men. The Phase 2a open-label, dose-escalating single and multiple dose study enrolled 12 males. Results from the Phase 2a clinical study demonstrated the feasibility of a once daily dosing with LPCN 1111 in hypogonadal men and a good dose response. Additionally, the study confirmed that steady state is achieved by day 14 with consistent inter-day performance observed on day 14, 21 and 28. No subjects exceeded Cmax of 1500 ng/dL at any time during the 28-day dosing period on multi-dose exposure. Overall, LPCN 1111 was well tolerated with no serious AE’s reported.
Lipocine has also completed a preclinical toxicology study with LPCN 1111 in dogs. In February 2018 the company had a meeting with the FDA to discuss these preclinical results and to discuss the Phase 3 clinical study and path forward for LPCN 1111. Based on the results of the FDA meeting, additional pre-clinical or clinical trials may be required before a Phase 3 clinical study can be initiated. Additionally the FDA requested that an ABPM clinical study be conducted. Based on its capital resources and the clinical status of its product candidates, the company will primarily focus its efforts in 2018 on TLANDO. The company do not anticipate the initiation of a Phase 3 study with LPCN 1111 to occur in 2018 unless and until additional capital is secured or the product candidate is out-licensed.
LPCN 1107: An Oral Product Candidate for the Prevention of Preterm Birth
The company believe LPCN 1107 has the potential to become the first oral hydroxyprogesterone caproate (“HPC”) product indicated for the reduction of risk of preterm birth (“PTB”) in women with singleton pregnancy who have a history of singleton spontaneous PTB. Prevention of PTB is a significant unmet need as ~11.7% of all U.S. pregnancies result in PTB (delivery less than 37 weeks), a leading cause of neonatal mortality and morbidity.
Lipocine has completed a multi-dose PK dose selection study in pregnant women. The objective of the multi-dose PK selection study was to assess HPC blood levels in order to identify the appropriate LPCN 1107 Phase 3 dose. The multi-dose PK dose selection study was an open-label, four-period, four-treatment, randomized, single and multiple dose, PK study in pregnant women of three dose levels of LPCN 1107 and the injectable intramuscular ("IM") HPC (Makena®). The study enrolled 12 healthy pregnant women (average age of 27 years) with a gestational age of approximately 16 to 19 weeks. Subjects received three dose levels of LPCN 1107 (400 mg BID, 600 mg BID, or 800 mg BID) in a randomized, crossover manner during the first three treatment periods and then received five weekly injections of HPC during the fourth treatment period. During each of the LPCN 1107 treatment periods, subjects received a single dose of LPCN 1107 on Day 1 followed by twice daily administration from Day 2 to Day 8. Following completion of the three LPCN 1107 treatment periods and a washout period, all subjects received five weekly injections of HPC. Results from this study demonstrated that average steady state HPC levels (Cavg0-24) were comparable or higher for all three LPCN 1107 doses than for injectable HPC. Additionally, HPC levels as a function of daily dose were linear for the three LPCN 1107 doses. Also unlike the injectable HPC, steady state exposure was achieved for all three LPCN 1107 doses within seven days. Lipocine has also completed a proof-of-concept Phase 1b clinical study of LPCN 1107 in healthy pregnant women in January 2015 and a proof-of-concept Phase 1a clinical study of LPCN 1107 in healthy non-pregnant women in May 2014. These studies were designed to determine the PK and bioavailability of LPCN 1107 relative to an IM HPC, as well as safety and tolerability.
A traditional pharmacokinetics/pharmacodynamics (“PK/PD”) based Phase 2 clinical study in the intended patient population is not expected to be required prior to entering into Phase 3. Therefore, based on the results of its multi-dose PK study the company had an End-of-Phase 2 meeting with the FDA as well as other guidance meetings with the FDA to define a Phase 3 development plan for LPCN 1107. During the End-of-Phase 2 meeting and subsequent guidance meetings, the FDA agreed to a randomized, open-label, two-arm clinical study to include a LPCN 1107 arm and a comparator IM arm with treatment up to 23 weeks. The FDA also provided preliminary feedback on other critical Phase 3 study design considerations including: positive feedback on the proposed 800 mg BID Phase 3 dose and dosing regimen; confirmation of the use of a surrogate primary endpoint focusing on rate of delivery less than 37 weeks gestation rather on clinical infant outcomes; acknowledged that the use of a gestational age endpoint would likely lead to any FDA approval, if granted, being a Subpart H approval; and, recommended a non-inferiority study margin of 7% with interim analyses. A standard statistical design for a NI study based on the FDA feedback, a NI margin of 7% for the primary endpoint may require ~1,100 subjects per treatment arm with a 90% power. However, based on the FDA’s suggestion of including an interim analysis in the NI design, an adaptive study design is under consideration that may allow for fewer subjects. The company submitted the initial LPCN 1107 Phase 3 protocol to the FDA via a SPA in June 2017 and have received multiple rounds of FDA’s feedback. Agreement with the FDA on the Phase 3 protocol via SPA has not occurred and will not occur until results from a planned food-effect study with LPCN 1107 are reviewed by the FDA. Final agreement with the FDA on the Phase 3 protocol, if reached, may or may not confirm the FDA’s preliminary feedback on the Phase 3 design. Additionally, manufacturing scale-up work for LPCN 1107 has been completed. Based on its capital resources and the clinical status of its product candidates, the company plan to primarily focus its efforts in 2018 on TLANDO. Lipocine is not anticipating the initiation of a Phase 3 study with LPCN 1107 to occur in 2018 unless and until additional capital is secured or the product candidate is out-licensed.
The FDA has granted orphan drug designation to LPCN 1107 based on a major contribution to patient care. Orphan designation qualifies Lipocine for various development incentives, including tax credits for qualified clinical testing, and a waiver of the prescription drug user fee when the company file its NDA.
Research and Development
The company currently have three products in its development pipeline (TLANDO, LPCN 1111 and LPCN 1107) and the company continue to conceptualize and discuss new indications for current products as well as new development opportunities. In 2017 and 2016, the company spent $11.0 million and $8.1 million, respectively, on research and development.
Testosterone Market Overview
The gel-based testosterone replacement products that are currently available include AndroGel®, marketed by AbbVie, and Endo’s Testim® and Fortesta® along with their respective authorized generics. Transdermal patches include Allergan’s Androderm®. Intramuscular forms of testosterone also exist although commercialized mostly in generic forms by multiple companies and in branded form as Aveed® by Endo. Additionally, Endo markets the buccal testosterone replacement therapy Striant® and the Testopel® implantable testosterone pellets, which it acquired from Auxillium in 2015. Also, Aytu BioScience Inc. markets an intranasal testosterone therapy Natesto®, which it licensed from Acerus Pharmaceuticals in 2016.
Testosterone gels dominate the testosterone replacement therapy market in terms of sales dollars while intramuscular injections have the highest market share in the testosterone replacement market in terms of annual prescriptions. While gels are a widely-used form of testosterone replacement therapy, there is a risk of transference; additionally, the gels are messy to apply and have significant compliance issues leading to high rates of discontinuance among patients. Additionally, certain intramuscular injections have the potential to cause pulmonary embolisms as well as cause injection site reactions, scarring, pain and risk of infection in patients. The company believe, a safe and effective oral therapy could potentially increase patient convenience and compliance, while eliminating the testosterone transference risk associated with gels and injection site reaction of injectables. .
The FDA has granted a therapeutic equivalence ("TE") rating of AB to “generic” versions of approved products which have been approved via a 505(b)(2) NDA. In July 2014, FDA granted the AB rating to Perrigo’s 1% testosterone gel drug product (NDA 203098) approved in January 2013, and a BX rating to Teva’s 1% gel drug product (NDA 202763) approved in February 2012. Each are versions of AbbVie’s AndroGel 1.0% and employed 505(b)(2) submissions citing AndroGel as their reference listed drugs ("RLD"). Teva’s version was found to be bioinequivalent to AndroGel, hence the BX rating. Upsher-Smith Laboratories also received approval for a version of Auxilium’s Testim (Vogelxo™; NDA 204399) in June 2014 using the same pathway. In January of 2015, the FDA determined that Vogelxo™ is therapeutically equivalent to Testim and received an AB rating. In August 2015, the FDA granted AB rating to Perrigo’s 1.62% testosterone gel drug product (NDA 204268) which also received FDA approval in August 2015. Eli Lilly and Acrux’s Axiron had patent expiry in February 2017. On July 6, 2017, Acrux confirmed that a generic version of Axiron® Topical Solution, 30 mg/1.5 mL (Testosterone Topical Solution, 30 mg/1.5 mL). has been launched in the United States by Perrigo Company plc. Acrux also confirmed the availability of an authorized generic version of Axiron in the United States, through a marketing and distribution agreement between Eli Lilly and Company and a leading authorized generics company.
Other Therapies in Development
Recently there has been increased interest in developing oral testosterone replacement therapies as well as testosterone therapies which are not considered testosterone replacement and as such will need to achieve efficacy endpoints in addition to endpoints related to serum testosterone levels that are required for testosterone replacement therapies.
Clarus Therapeutics, Inc. has completed three Phase 3 clinical studies. Clarus originally filed an NDA in early 2014 with Jatenzo® (formerly Rextoro® and CLR-610), a twice-daily oral softgel capsule of TU, as a testosterone replacement therapy for the treatment of hypogonadism in men. On September 18, 2014, Clarus and the FDA had an Advisory Committee meeting to evaluate the safety and efficacy of Jatenzo. 18 of the 21 members of the Advisory Committee voted that the overall benefit/risk profile of Jatenzo is not acceptable to support approval for T-replacement therapy. The PDUFA date for the Jatenzo NDA was November 2014 with the FDA issuing a CRL. Subsequent to receiving the CRL, Clarus completed another Phase 3 clinical study and subsequently resubmitted its NDA for Jatenzo in June 2017. An Advisory Committee meeting was held for Jatenzo on January 9, 2018 in which the BRUDAC voted nine in favor and ten against the acceptability of overall benefit/risk profile to support approval of Jatenzo as a TRT. The FDA concluded that Jatenzo increased blood pressure in a clinically significant manner compared to Axiron, despite more Jatenzo -treated subjects having escalation of antihypertensive therapies. Jatenzo also increased heart rate, which may amplify the blood pressure effects on cardiovascular risk.
Antares Pharma, Inc. is developing a testosterone enanthate auto-injector administered subcutaneously once each week. The product candidate completed a double-blind, multiple-dose, 12-week efficacy and 52-week safety Phase 3 study in October 2015 and completed a dose-blinded, multiple-dose, concentration controlled 28-week safety and pharmacokinetic study in June 2016. Antares filed an NDA with the FDA for XYOSTED™ (testosterone enanthate) injection, their testosterone auto-injector, in December 2016. On October 20, 2017, Antares announced that it had received a CRL from the FDA regarding its NDA for XYOSTED™ injection. The CRL indicated that the FDA cannot approve the Antares NDA in its present form and identified two deficiencies related to clinical data. Based on findings in two clinical studies, the FDA is concerned XYOSTED could cause a clinically meaningful increase in blood pressure. Additionally, the CRL also raised a concern regarding the occurrence of depression and suicidality.
Marius Pharmaceuticals is developing an oral testosterone undecanoate as a testosterone replacement therapy for the treatment of hypogonadism in men and in the treatment of Constitutional Delay of Growth and Puberty in adolescent boys (14-17 years of age). The product candidate has completed Phase 2 clinical trials in hypogonadal males and an end of Phase 2 meeting has been requested of the FDA. Marinus is also currently conducting a 52-week Phase 3 study with an active comparator for the TRT indication.
Novartis is currently developing BGS649, an aromatase inhibitor, as a testosterone therapy for the treatment of obese, hypogonadotropic hypogonadal men.
TesoRx Pharma LLC is developing a potential once-daily oral bio-identical testosterone, TSX-002, in the treatment of Constitutional Delay of Growth and Puberty. Phase 2 clinical studies have been completed. TesoRx is also developing a next generation potential once-daily, oral testosterone undecanoate product candidate, THG-1001, as a testosterone replacement therapy for the treatment of hypogonadism in men. An IND has been filed for THG-1001 and TesoRx has commenced enrollment for a Phase1/2a clinical trial in patients with hypogonadism.
Hydroxyprogesterone caproate, or HPC, Preterm Birth, or PTB, Market Overview
PTB is defined as delivery before 37 weeks of gestation. The only approved therapy for prevention of PTB in women with a prior history of at least one preterm birth (~180,000 pregnancies annually) is a weekly intramuscular injection of hydroxyprogesterone caproate, marketed by AMAG Pharmaceuticals, Inc. under the brand name Makena®. The FDA granted a 7-year orphan drug exclusivity to Makena in February 2011 because the product is intended to treat “rare diseases or conditions” defined as a condition that affects fewer than 200,000 persons in the United States which expired in February 2018. AMAG is also developing a potential subcutaneous autoinjector for Makena that received FDA approval on February 14, 2018. Treatment with Makena is initiated in pregnant women between week 16 and week 20 of pregnancy and is continued until up to delivery or week 37, whichever is earlier. The intramuscular injection is administered by a healthcare provider using a 21-gauge needle into the gluteus muscle, alternating sides each week. The intramuscular injections are associated with significant pain, discomfort and associated injection site reactions.
AMAG Pharmaceuticals acquired Makena from Lumara Health Inc. in November 2014 for an upfront consideration of $675.0 million ($600.0 million in cash and $75.0 million in AMAG Pharmaceuticals stock) and additional contingent consideration of up to $350.0 million based on achievement of certain sales milestones. Net sales of Makena in 2017 were estimated to be $387.2 million.
On March 3, 2016, the company entered into a Commercial Manufacturing Services and Supply Agreement (the “Manufacturing Agreement”) with M.W. Encap Ltd. (“Encap”), a United Kingdom based contract manufacturer, a division of Capsugel Dosage Form Solutions which is a subsidiary of Lonza. Pursuant to the Manufacturing Agreement, Encap has agreed to manufacture and supply bulk commercial quantities of TLANDO. From the effective date of the Manufacturing Agreement through the fifth anniversary of the date that FDA approval is obtained for the sale and marketing of TLANDO in the United States unless earlier terminated, Lipocine has agreed to purchase a minimum of TLANDO on an annual basis from Encap once the company receive commercial approval on the basis of a 12-month rolling commercial forecast in which the first 3 months of each rolling forecast are binding on it. Such forecast may be subsequently increased or decreased by it pursuant to the terms of the Manufacturing Agreement.
In general, the company may terminate the Manufacturing Agreement without incurring any fees or costs upon 90 days written notice or immediately if Encap is not able to meet its reasonable requirements of TLANDO. The company and Encap may each terminate the Manufacturing Agreement upon a material breach of the Manufacturing Agreement by the other party, so long as the other party has not cured such breach within a defined period after written notice of the breach by the non-breaching party or in the event the other party becomes insolvent or goes into bankruptcy, liquidation or receivership. Encap may terminate the Manufacturing Agreement if Lipocine has not placed a firm order for TLANDO within a defined period of time from the date of FDA approval of TLANDO. Additionally, Encap may terminate the Manufacturing Agreement without cause upon the provision of written notice within a defined period of time advance written notice.
Additionally, the company entered into an Agreement for the Manufacture of Testosterone Undecanoate Liquid Fill Capsules and the Conduct of an ICH Stability Study in Support of Product Registration with Encap pursuant to which Encap manufactured and supplied to it a total of six lots of TLANDO capsules under current good manufacturing practices. These lots were used in Lipocine’s Phase 3 study for TLANDO. Under the agreement, Encap is also conducting an International Conference on Harmonisation stability program on all six capsule lots in support of its resubmitted NDA filing for TLANDO. If Encap is unable to produce sufficient capsules for its future clinical trials or to support demand for TLANDO if it becomes commercially available, its revenue and profitability would be adversely affected.
Drug Delivery Technologies for Lipophilic Drug Substances
TLANDO is an oral formulation of the lipophilic prodrug testosterone undecanoate, utilizing its proprietary technology for improved delivery of lipophilic therapeutic agents. The company's patent portfolio is directed to various types of compositions and methods for delivery of lipophilic drugs, which are drugs that are soluble in lipids. As of March 6, 2018, the company otherwise own or control 20 issued U.S. patents, 31 pending U.S. patent applications, 20 issued foreign patents, 50 pending foreign patent applications and 3 pending Patent Cooperation Treaty (“PCT”) applications. Of the above, Lipocine has 12 issued U.S. patents, 25 pending U.S. patent applications, 20 issued foreign patents, 6 pending foreign patent applications and 1 PCT applications relating to various aspects of TLANDO.
The company also hold license rights in fields other than cough and cold, to 2 U.S. patents and 1 U.S. applications (and related foreign patents and applications) that the company previously assigned to Spriaso LLC, which could be possibly used with future product candidates.
The company's issued U.S. Patent No. 6,267,985 covers pharmaceutical compositions comprising a therapeutic agent solubilized in a triglyceride, and it is expected to expire in 2019. Lipocine has corresponding patents in Australia, Canada, and New Zealand. These corresponding foreign patents are all expected to expire in 2020. The company's issued U.S. Patents No. 6,569,463 and 6,923,988 cover various aspects of pharmaceutical compositions comprising a hydrophobic active ingredient admixed with a hydrophilic surfactant and other components (for example, a lipophilic additive). These issued patents are expected to expire in 2019 and 2020, respectively, and if pending U.S. applications were to issue as patents, their expected expiration would be in 2019. Lipocine has corresponding patents in Canada which are expected to expire in 2020.
Lipocine has 2 issued US patents (U.S. Patent No. 8,865,695 and U.S. Patent No. 8,778,922), 5 pending U.S. patent applications, one issued patent in each of Canada, Japan, Australia and Mexico and 4 corresponding foreign patent applications (one each in Europe, Hong Kong, Brazil, and India) directed to oral pharmaceutical compositions comprising a testosterone ester and methods of their use. These patents and applications, if they issue, are expected to expire in 2029 in the U.S. and 2030 in foreign jurisdictions.
Lipocine has pending U.S. patent applications, 3 foreign patents (one each in Australia, Canada and New Zealand) directed to oral dosage forms comprising a drug, a solubilizer, and a release modulator. The pending U.S. patent applications, if they issue, are expected to expire as early as 2023, and the foreign patents are expected to expire in 2026.
Lipocine has pending U.S. patent applications directed to pharmaceutical compositions comprising a sex hormone with corresponding foreign patents in Australia, Canada and Japan. These applications, if they issue, are expected to expire in 2019, while the foreign patents are expected to expire in 2024.
Lipocine has 5 issued patents and 6 pending U.S. applications directed to high strength capsule formulations of testosterone undecanoate and methods of their use. These patents and applications, if they issue, are expected to expire in 2030.
Lipocine has 2 pending U.S. patent application related to solid dosage forms that have testosterone undecanoate. This application, if it issues, is expected to expire in 2030.
Lipocine has pending US applications related to fixed dose dosing regimens, food effects, methods of treatment and high-loading formulations. The high-loading formulations application is also pending in China and Russia.
The company currently do not have patent protection for TLANDO in many countries, including territories such as India, Russia, and China, and the company will be unable to prevent patent infringement in those countries unless the company can file patent applications and obtain patents in those countries that cover TLANDO. The company currently have 1 PCT application pending which can be entered into the national phase of such countries to protect TLANDO. Additionally, the 10 U.S. patents that could be listed in the FDA Orange Book for TLANDO are expected to expire in 2019, 2020, 2029 and 2030. If Lipocine is marketing the TLANDO product at the time the patents expire and have no other issued U.S. patents covering the product, then the company will lose certain advantages that come with FDA Orange Book listing of patents and will no longer be able to prevent others in the U.S. from practicing the inventions claimed by the 10 patents.
US Patent No. 8,951,996 (along with 4 additional related US issued patents) and 2 pending U.S. patent applications with corresponding counterpart applications filed in Australia (granted), Brazil, Canada (granted), China, Europe, India, Israel (granted), Japan, Mexico (granted), New Zealand (granted), Russia (granted), South Africa (granted) and South Korea are related to its LPCN 1107 product candidate. Lipocine has an additional PCT application which was entered into Australia, Brazil, China, Europe, Indonesia, Israel, Japan, Mexico, New Zealand, Philippines, and South Africa, as well as a corresponding US application. These U.S. patents and pending U.S. patent applications, if they issue, are expected to expire as early as 2031, and the foreign patent applications if they issue, are expected to expire in 2032.
US applications with corresponding counterparts filed in Argentina, Australia, Brazil, China, Canada, Europe, India, Israel, Japan, Mexico, New Zealand, Paraguay, South Africa, South Korea, Taiwan, Uruguay and Venezuela and 1 PCT applications as well which can be filed into other foreign jurisdictions at the appropriate time, are being prosecuted to protect its LPCN 1111 product candidate. Lipocine has 2 issued US patent related to LPCN 1111 that are expected to expire in 2035. The U.S. patent applications, if they issue, are expected to expire as early as 2029, and the foreign patent applications if they issue, are expected to expire as early as 2034.
The company expect to file new patent applications in the future in an attempt to further cover to various aspects of its products and product development.