Affymax Tanks as Investors Worry About Safety of Anemia Drug: Biotech's Latest Mishaps

by: The Burrill Report
Shares of Affymax (NASDAQ:AFFY) tumbled 65 percent on news that despite a set of late-stage trials of its anemia drug Hematide that showed it was not inferior to Amgen’s (NASDAQ:AMGN) Epogen or Aranesp, a subgroup of pre-dialysis patients had a statistically significant increase in cardiovascular events. That raised concerns among some investors that it could delay approval of the drug or prevent approval of its use in that population of patients. Affymax CEO Arlene Morris called the completion of the late-stage studies a “key milestone.” She said the company is continuing to evaluate the data, in particular the non-dialysis studies, and the impact on the timing of when it would submit an application to the U.S. Food and Drug Administration for approval to market the drug.

Pfizer (NYSE:PFE) said it is removing its leukemia drug Mylotarg from the market after a study found higher death rates and no benefit for patients using the drug. The approval of Mylotarg in the United States was granted under FDA's accelerated approval regulations based on overall response rate in three non-comparative studies and required submission of additional data to confirm clinical benefit. The required post-approval study combining chemotherapy and Mylotarg did not demonstrate improved survival compared with chemotherapy alone in patients with previously untreated acute myeloid leukemia.

Pfizer said it has suspended development of tanezumab, a monoclonal antibody for the treatment of osteoarthritis. The decision followed a request by the U.S. Food and Drug Administration and comes after reports of a small number of tanezumab patients experiencing the worsening of osteoarthritis leading to joint replacement. To date, this adverse event has not been observed in non-osteoarthritis patient populations taking tanezumab, the company said. The clinical hold includes both the suspension of recruitment of new patients and the dosing of existing patients in the osteoarthritis program, as well as patients with osteoarthritis in other studies. The FDA has asked Pfizer to present its assessment of the potential implications of the adverse events in the osteoarthritis program for the other tanezumab clinical programs involving non-osteoarthritis patients, which include patients with cancer pain, interstitial cystitis, chronic low back pain and painful diabetic peripheral neuropathy. The company is working with the agency to determine the appropriate course of action.
Basilea Pharmaceutica (OTC:BPMUF) said that following a request for re-examination from the Johnson & Johnson (NYSE:JNJ) subsidiary Janssen-Cilag International, the European Committee for Medicinal Products for Human Use confirmed its previous rejection of the Marketing Authorization Application for ceftobiprole for the treatment of complicated skin and soft tissue infections. The agency indicated that, although the study results suggested that the medicine was beneficial to patients, it was concerned about the reliability of the results. The committee recommended that, in light of the uncertainty surrounding the results, ceftobiprole should not be granted marketing authorization. In February, the agency said that inspections had shown that the late-stage studies supporting the application had not been conducted in compliance with good clinical practice in some sites. Full rights to ceftobiprole will be transferred from Cilag back to Basilea.

Exelixis (NASDAQ:EXEL) said it had regained rights to its experimental cancer drug XL184 after Bristol-Myers Squibb (NYSE:BMY) had ended its development agreement over the so-called MET inhibitor. Under the agreement, BMS and Exelixis had originally agreed to certain clinical development plans, and Exelixis maintained key rights regarding timing and funding of current and future clinical trials. Given the recent progress of BMS' wholly-owned oncology pipeline and positive data generated by XL184, Exelixis and BMS were not able to agree on the scope, breadth and pace of the ongoing clinical development of XL184. BMS will make a payment to Exelixis of $17 million in connection with the return of XL184. “We certainly understand BMS' need to make pipeline and prioritization decisions, but from Exelixis' perspective, XL184 is our most advanced compound, the data are encouraging, and we need to rapidly develop the compound in indications justified by the data,” says George Scangos, CEO of Exelixis.