Puma Biotechnology, Inc. (NYSE: PBYI) is a development-stage biopharmaceutical company that develops innovative products for the treatment of various forms of cancer. The company has become popular among investors and the scientific community back in July 2014, when the company’s main drug candidate, Neratinib, demonstrated effectiveness by improving disease-free survival of breast-cancer patients. Since then, the company couldn’t repeat the same impressive results. Investors do anticipate phase 2 data completion by the end of this month to see if the company can repeat its success.
Before discussing the phase 2 data, it’s important to mention Puma’s failures. Neratinib is being tested in several clinical trials, and the results from one of them were reported recently. On May 13th, the company published abstracts from a phase 3 trial of Neratinib called ExteNET, for the treatment of early stage HER 2-positive breast cancer. The trial is considered to be a clinical failure, and the stock plummeted 20% after the abstracts were published. The first issue is the unpleasant side effects. Neratinib caused grade 3 diarrhea in 40% of the patients in the trail.
The second issue is that the drug failed to show significant difference in results comparing to placebo in both primary and secondary endpoints. The primary endpoint for the trial was to show reduction in invasive disease free survival (DFS). The separation between the two year DFS rates was 93.9% for Neratinib and 91.6% for placebo, only 2.3% difference. The secondary endpoint of the trial was disease-free survival including ductal carcinoma in situ (DFS-DCIS). The difference in 2-year DFS-DCIS rates was once again, not significant: 93.9% for Neratinib and 91.0% for placebo, a 2.9% difference.
The final data results from the ExteNET trial where released on June 1st, and the stock crashed additional 13% the day after.
The phase 2 trial that is anticipated to be completed by the end of this month is a neoadjuvant treatment for patients with HER2+ positive breast cancer, and has a different primary endpoint – to achieve a pathological complete response rate in treatment of breast and axillary lymph nodes. The trial is a randomized trial of Neratinib, Taxol (a drug on trial for the treatment of lymphoma), Herceptin (an antibody for the treatment of certain breast cancers)
This trial is funded by NSABP (National Surgical Adjuvant Breast and Bowel Project), and it is a very important trial for, Puma, as the company can prove once again the effectiveness of its product. The anticipated treatment duration is expected to be 3 month.
The market size of neoadjuvant treatment for patients with HER2+ positive breast cancer is, sadly, growing. Approximately 36,000 new patients are diagnosed in the U.S every year, and about 34,000 in Europe. This is a billion dollar market.
Puma Biotechnology is in an excellent financial position, with no debt and about $310 million cash. The company burned more than $50 million on operating activities during the first quarter of 2015, significantly more than in previous quarters since new trials have been initiated and trial enrollment processes have accelerated.
Stay tune as we continue our coverage on Puma on weather it will manage to impress once again.