Ariad and Merck Meet Primary Endpoint and to Submit for FDA Approval

Ariad Pharmaceuticals (ARIA) and Merck (MRK) are co-developing a small molecule inhibitor of the mammalian target of rapamycin (mTOR) called ridaforolimus.  ARIA announced that ridaforolimus has shown to reduce the cancer progression by 28 percent and increased progression free survival by about 3 weeks.  The most frequent adverse effects were mouth sores, fatigue, diarrhea and  low platelets.  MRK plans to submit for FDA approval this year. ARIA's stock price jumped 30% after the announcement.  ARIA has no currently approved drugs.  ARIA will be eligible for milestone and royalty payments. ARIA's current stock price is nearly three times higher than one year ago. 

If approved, it would be the 2nd in class drug for treatment of cancer; temsiroliums (Torisel) was approved by FDA for treatment of renal cell carcinoma and is manufactured by Wyeth, now owned by Pfizer.  Torisel showed slightly better results, but it was in a different type of cancer and renal cell carcinoma is known for having mTOR dysregulation.  Rapamycin is another drug in this class, but is approved for prevention of transplant rejection.

mTOR is a protein that integrates signals from insulin, growth factor, and cell division pathways.  It is often dysregulated in cancers and is a potential target for treatment.  It interacts with othere pathways and proteins that are involved in various forms of cancer such as the Abl gene, which is translocated and fused with Bcr in chronic myelogenous leukemia.  Despite the inter-connectivity with other pathways, the adverse effects are minimal and not of great concern.  This can be attributed to the specificity of the drugs.  ARIA and MRK are also conducting ridaforolimus clinical trials in breast, lung, prostate, pediatric, endometrial, and other solid tumors. Most of these trials are in Phase II.  

There is a huge potential for ridaforolimus and can become ubiquitous in oncology as doxorubicin.  With a great tolerability profile for a cancer drug and continuing good results from clinical trials, ridaforolimus can be very profitable for ARIA and MRK.  Also, investors should monitor results from clinical trials of both ridaforolimus and Torisel and compare results for the same types of cancers.  These trials are generally conducted in patients who have failed other therapies, so they are in the worst condition.  Results from studying ridaforolimus as a first line therapy should show better results.