Tekmira's Ebola drug comes up short in Phase II

Tekmira's ($TKMR) in-development treatment for Ebola virus failed to move the needle in a midstage trial, leading the drugmaker to halt the study and sending its share value downward.

The drug, TKM-Ebola-Guinea, is an RNAi therapeutic designed to silence the viral genes that allow a particular strain of Ebola to proliferate. Looking at data from a West African Phase II trial, however, Tekmira noted that its treatment "was not likely to demonstrate an overall therapeutic benefit" and promptly halted enrollment.

Despite the treatment flunking a scheduled futility analysis, Tekmira cautions that it can't make a final decision on the candidate until full trial results are available. The news sent the biotech's shares down as much as 15% on Friday.

The drug is a reformulation of Tekmira's TKM-Ebola that is designed to target the Guinea strain of the virus, responsible for the most recent outbreak. TKM-Ebola, which is designed for Kikwit strain, is in Phase I development under a $140 million contract with the U.S. Department of Defense. After months of delay, Tekmira resumed that trial in April after the FDA signed off on some safety issues that had previously forced the company to pause development.

Tekmira's shares have soared and plummeted along with TKM-Ebola's up-and-down development over the past year, fueled by the now-subsided outbreak of the virus in West Africa. Beyond its work in Ebola, the company's pipeline is largely focused on hepatitis B, for which it has 8 candidates in various stages of early development. Tekmira's RNAi platform also includes potential treatments for cancer and metabolic disease.

Meanwhile, the waning numbers of Ebola cases are making it difficult for global outreach organizations and pharma organizations to complete trials for new treatments and vaccines for the virus. Companies including Johnson & Johnson ($JNJ), GlaxoSmithKline ($GSK) and Merck ($MRK) are working with health authorities to study potential cures in Africa, and declining rates of infection--while unquestionably good for the continent--are making enrollment difficult.

- read the statement