Catalyst Pharmaceutical Partners, Inc. (Nasdaq: CPRX) is a biopharmaceutical company focused on the development and commercialization of prescription drugs targeting diseases of the central nervous system, with a focus on the treatment of drug addiction and epilepsy. Catalyst has two lead products in development; CPP-109 and CPP-115.
Its first product, CPP-109, is a formulation of vigabatrin. Vigabatrin has been marketed over the past decade by Sanofi-Aventis (SNY) under the brand name Sabril, as a secondary treatment for adult epilepsy and as a primary treatment for the management of infantile spasms. Prior to just last year, Sabril® was not approved for any uses in the U.S. The FDA has been hesitant to approve vigabatrin for use in the U.S., citing concerns about reports of retinal damage in patients.
This has been a hurdle for any new indications of vigabatrin. However, in August 2009, the FDA approved two NDAs from Ovation Pharmaceuticals (now Lundbeck (OTC:HLUKY)) for Sabril for the treatment of infantile spasms and as add-on therapy for adult patients with refractory complex partial epileptic seizures.
This change in FDA policy has opened the window for continued development of vigabatrin. Catalysts Pharmaceuticals version of vigabatrin, CPP-109, has been granted “Fast Track” status by the U.S. Food & Drug Administration (FDA) for the treatment of cocaine addiction. This indicates that the FDA has recognized the potential for CPP-109 to make a significant contribution towards treating addiction, without a safety blockade vigabatrin has experienced in the past. This is because Catalyst Pharmaceuticals has provided sufficient data that CPP-109 works without the apparent retinal damage side effects typically associated with vigabatrin. In fact, the National Institute on Drug Abuse (NIDA) has proposed to give Catalyst nearly $10 million to conduct a U.S. Phase II(b) clinical trial evaluating CPP-109. Certainly this is a vote of confidence for a CPP-109.
CPP-109 and vigabatrin works by indirectly lowering the level of dopamine in the brain; specifically, GABA — gamma-aminobutyric acid — a neurotransmitter in the brain that inhibits the release of dopamine. Normally, the release of dopamine in the brain causes the "high" or exaggerated sense of pleasure associated with drug abuse. GABA, however, is broken down by GABA transaminase (GABA-T). Vigabatrin works by inhibiting GABA-T and consequently by increasing the level of GABA. This then lowers the level of dopamine and turns off the "high", and prevents drug use from being pleasurable to the user.
Over the years, vigabatrin has shown success in early trials, suggesting it might be effective against stimulant addiction. Previous studies in established animal models of addiction, involving both rats and primates, have shown that vigabatrin interrupts the neural mechanisms essential for addiction. In preclinical studies, vigabatrin prevented the characteristic drug-seeking behavior of addicted animals. Three human trials of vigabatrin have been completed in patients addicted to cocaine or methamphetamine. Data from these three trials provide clinical evidence of vigabatrin's potential as a safe and effective treatment for patients with these addictions.
Unlike alcohol and heroin, cocaine and speed have proven particularly resistant to treatment with other drugs designed to diminish craving. Since there are no FDA-approved medications for cocaine or methamphetamine addiction, current treatment strategy centers on cognitive and behavioral approaches.
From NIDA's point of view, a drug that effectively reduced craving in abstinent cocaine and methamphetamine addicts would dramatically improve addiction treatment. From a pharmaceutical company's point of view, it would open up a potentially large and lucrative market. NIDA has been the major supportor of vigabatrin trials, sponsoring two major development programs for vigabatrin for the treatment of cocaine and/or methamphetamine addiction.
NIDA's bet on Catalyst's CPP-109:
A Cooperative Research and Development Agreement (CRADA) is a legal agreement between a government entity and one or more non-government parties, such as private industry and academia. CRADAs offer both parties an opportunity to leverage each other’s resources when conducting mutually beneficial research and development (R&D).
In 2007, prior to its acquisition by Lundbeck, Ovation Pharmaceuticals signed a five-year CRADA with NIDA to study the use of vigabatrin for the treatment of cocaine and methamphetamine dependence. The U.S. Food and Drug Administration (FDA) has given Fast Track designation to vigabatrin. Under the CRADA, NIDA and Lundbeck (Ovation) were to jointly design and implement preclinical studies as well as clinical trials to assess the efficacy and safety of vigabatrin in cocaine and methamphetamine abusers. However, no direct funding by NIDA was provided, and no developments from this collaboration have been reported since this initial announcement. Lundbeck does not report a clinical development program for Sabril in this indication. The completed and ongoing trials for vigabatrin (NCT00506935, NCT00626834) are run by NIDA, not Lundbeck. This collaboration seems to have dissolved, as there have not been any clinical trials started nor updates in years.
However, NIDA is proposing to actively support CPRX to conduct its U.S. Phase II(b) clinical trial evaluating CPP-109 for the treatment of cocaine addiction. Under the preliminary agreement, NIDA will provide the most substantial resources for the estimated $10 milllion cost of the trial. CPRX will contribute approximately $2.5 million in costs (including study medication, patient recruitment costs and certain trial expenses), and NIDA will supply the rest.
Much of the research on vigabatrin to treat addiction has emerged from work performed over the last 12 years at the Brookhaven National Laboratory. Brookhaven holds various patents relating to its research findings. Catalyst has obtained from Brookhaven an exclusive worldwide license for nine patents in the United States for all rights to use or sell vigabatrin for the treatment of addiction to cocaine, methamphetamine, prescription pain medications, heroin, nicotine and other addictive drugs. In addition, Catalyst's license includes rights to Brookhaven's foreign patents or patents pending in more than 30 countries. Catalyst also acquired worldwide rights to a related patent held by Northwestern University. Together, these patents place CPRX as the leader using vigabatrin-based therapy to treat addiction and a natural choice for NIDA to collaborate with.
Catayst has run previous trials studying CPP-109 (trials NCT00527683, NCT00730522, and NCT00611130). However, in 2009 CPP-109 failed in a phase IIa trial for treatment for cocaine addiction. The results demonstrated that the drug did not help addicts stay cocaine-free. As a result, CPRX shares dropped from the $2 range to an all time low of 39 cents. Despite this disaster, Catalyst stated that it will continue to develop CPP-109 for the treatment of cocaine and methamphetamine addiction.
After post-hoc analyses of CPP-109 levels in urine samples collected during the study, Catalyst concluded that less than 40% of the trial subjects were medication compliant (these are drug addicts after all, self-compliance is difficult). As a result, the study was inadequately powered to test the protocol-specified efficacy hypothesis . When corrected for poor medication compliance, the major metabolite of cocaine measured in urine collected from subjects were consistently lower in the CPP-109 treatment group, (an objective measure of daily cocaine usage); and the patients demonstrated 3.5 times reduction in cocaine usage days (an objective measure of dependence severity).
This analysis makes the response ratios in these patients very significant, despite the failure in the overall pooled trial results (the results were published in The American Journal of Psychiatry). Catalyst’s decision to continue the development of the drug for both indications was supported by a panel of experts who met and agreed with the company's conclusion that there was sufficient evidence of safety and efficacy to justify further development of CPP-109. Catalyst presented this post-hoc analysis to NIDA. NIDA supported this conclusion and as a result, has proposed to fund the majority of the phase IIb trial for CPP-109.
Catalyst's plans for CPP-109 and other follow up drugs:
Patrick J. McEnany, Chief Executive Officer of Catalyst, stated,
There remains a tremendous unmet medical need for cocaine and methamphetamine addicted patients, and we believe a safe and effective patient-specific treatment may generate considerable interest among regulatory authorities, patients, physicians, investors and potential strategic partners. Our next step will be to present our findings to NIDA, the investment community, and potential strategic partners to obtain the funding to conduct additional clinical trials. We remain optimistic about the prospects for CPP-109 going forward and we are committed to aggressively pursuing our two primary objectives: (i) the continued development of CPP-109 towards a pivotal Phase III trial; and (ii) completing a high-value partnership for the CPP-109 program. With the addiction market potentially exceeding $1 billion and growing, we believe CPP-109 is very competitively positioned from a safety and efficacy perspective. As a shareholder with a significant personal investment in the Company, my interests are aligned with the interests and concerns of every shareholder. I am deeply committed to building a successful Company.
Patrick J. McEnany is bullish about Catalyst’s future, as any CEO should be, but there is great cause for his bullishness. With approval for CPP-109 for the treatment of cocaine addiction, the company would have a corner on the market-- a $1 billion corner. If it can gain FDA approval for this indication, others are likely to follow, given the general role of GABA aminotransferase in many types of addictions. With the support of the FDA and NIDA, it seems that Catalyst has the support it needs. When the company completes the trial and shows the efficacy it saw in compliant patients in the phase IIa trial; and CPP-109 is on the fast track to approval, literally. Although NIDA support will end after completion of this trial, it is obvious than any number of major pharmaceutical companies would be willing to partner with CPRX to support at phase III trial to gain approval. With a current PPS of about 80 cents and market cap of $15 million, CPRX is a whole lot of bang for very little buck.
In 2010, CPRX will focus on developing CPP-109 for cocaine addiction. CPRX has stated that it believes that the Fast Track status from the FDA for CPP-109 for cocaine addiction may facilitate the regulatory approval process. Catalyst expects to execute a clinical trial agreement with NIDA in the near future, and to commence the trial in the summer of 2010. CPRX anticipates that an approximately 200 patient trial will take 18 months to complete. It will be conducted at eight leading addiction facilities across the United States. The clinical trial is designed to confirm the safety and efficacy of CPP-109 for the treatment of cocaine addiction. If successful, Catalyst believes it will qualify to be one of the adequate and well controlled trials to support approval of an NDA by the FDA.
In addition to CPP-109, earlier this year Catalyst also revealed the company's development plans for its novel drug CPP-115. CPP-115 will be tested for the treatment of epilepsy, including infantile spasms, and addiction. CPP-115 is a compound in a new class of therapies for a broad range of central nervous system illnesses that could benefit from the inhibition of GABA aminotransferase. CPP-115 has been shown to be at least 200 times more potent than vigabatrin. The increased potency could enable the development of superior or alternative dosage forms and routes of administration compared with Sabril. It may also have superior specificity to GABA aminotransferase and, possibly, a better side effects profile compared to Sabril. CPP-115 and other CPRX are the only known drugs currently in development having GABA aminotransferase inhibition as their primary mode of action. Catalyst is also seeking to develop additional therapies similar to CPP-115 for a broad range of central nervous system illnesses that could benefit from the inhibition of GABA aminotransferase.
Over the next year, Catalyst plans to advance the development of CPP-115 by completing a series of non-clinical studies designed to demonstrate critical safety and efficacy characteristics of CPP-115. CPRX states that by the end of the third quarter of 2010, most of the safety studies for CPP-115 are expected to be completed. Furthermore, by the end of this year, Catalyst expects to complete animal studies for screening of CPP-115 as a potential treatment for both epilepsy and drug addiction. Catalyst presented data for CPP-115 at the 2010 Epilepsy Pipeline Update Conference in February.
Catalyst also announced last Friday that on April 16th, it will discuss data from its phase II clinical trial to evaluate the safety and efficacy of Catalyst's drug CPP-109 (Vigabatrin) for treating cocaine dependence at the American Society of Addiction Medicine's (ASAM) 41st Annual Medical-Scientific Conference in San Francisco, CA. Dr. Somoza was the Coordinating Principal Investigator for the trial and will discuss data from Catalyst's U.S. Phase II trial evaluating CPP-109 to treat cocaine addiction.
For more information about the company and these events, go to www.catalystpharma.com/.
Disclosure: I have no position in CPRX