Alnylam Pharmaceuticals said this week that it has began a phase IIb trial of its siRNA-based respiratory syncytial virus drug ALN-RSV01 in adult lung transplant patients, on track with previous guidance.
In July, Alnylam released data from a phase IIa study of the drug, also in RSV-infected adult lung transplant patients, showing that ALN-RSV01 was safe and well tolerated (see RNAi News, 7/23/2009). At the time, the company also said that the data indicated a certain level of efficacy, but this demonstration was less robust than many industry watchers had expected.
Despite Cubist Pharmaceuticals, Alnylam's partner on the RSV program outside of Asia, having passed on developing ALN-RSV01 in favor of a second-generation version of the drug, Alnylam remained committed to the agent.
"Alnylam's new phase IIb study aims to repeat and extend the results we saw in our previous phase IIa study in the same patient population," Akshay Vaishnaw, the company's senior vice president of clinical research, said in a statement.
The new trial is a randomized, double-blind, placebo-controlled study in RSV-infected lung transplant patients with a primary endpoint of a reduction in incidence of new or progressive bronchiolitis obliterans syndrome, a complication of RSV infection, according to Alnylam.
Secondary endpoints of the trial include assessments for safety and additional measurements of efficacy, including anti-viral activity, recovery of lung function, and improvement in RSV symptoms.
The study is expected to enroll 76 patients who will all receive standard of care, with some receiving ALN-RSV01 administered as a 0.6 mg/kg dose by inhalation once daily for five days, the company added.