Alios BioPharma Reports Positive Results of Its Anti-RSV Nucleoside Analog AL-8176 in a Phase 2 Challenge Study in Adults Infected With Respiratory Syncytial Virus (RSV)

SOUTH SAN FRANCISCO, CA--(Marketwired - Jul 23, 2014) - Alios BioPharma, Inc., a biotechnology company developing proprietary therapeutics for respiratory viral diseases, today announced positive results from a randomized, double-blind, placebo-controlled Phase 2 challenge study of its oral anti-RSV nucleoside analog AL-8176. The study was conducted in healthy adult volunteers who were infected intranasally with respiratory syncytial virus (RSV). AL-8176 achieved its primary and secondary endpoints of reduction in viral load (p < 0.0002) and improvement in symptom scores (p < 0.02) as compared to placebo. AL-8176 was well tolerated with no discontinuations of study drug and no clinically significant laboratory abnormalities. 

"With no available effective therapies for RSV, results from this trial demonstrate significant promise for AL-8176, a first-in-class, novel nucleoside replication inhibitor, as a means to address the unmet medical needs of patients who suffer from this often devastating infection," said John DeVincenzo, MD, Professor of Pediatrics and Professor of Microbiology, Immunology and Biochemistry at the University of Tennessee School of Medicine. "The magnitude of viral load inhibition demonstrated by AL-8176 in the human challenge study is similar to viral load reductions seen with other nucleoside analogs used to treat viral diseases such as chronic hepatitis C. Given the emerging safety and efficacy profile of AL-8176, and experience in the use of other nucleoside analogues for management of other viral infections in patients including young children, further study is warranted and pediatric trials are currently underway."

The Alios study enrolled 62 healthy adults who received one of three dose regimens of AL-8176 or placebo over 5 days: 375 mg orally administered twice daily or 750 mg given as a single loading dose (LD) followed by twice daily maintenance doses (MD) of 150 mg or 500 mg. Administration of AL-8176 began approximately 12 hours after confirmation of RSV infection as determined by presence of RSV RNA in nasopharyngeal washes. In successfully infected subjects, marked immediate reduction in RSV viral load was observed following treatment in all three AL-8176 treated dose groups as compared to placebo where subjects exhibited a logarithmic increase in RSV RNA with a peak viral load at Day 3.5 following start of dosing. At discharge (Day 12), all subjects treated with AL-8176 were RSV RNA undetectable and remained RSV RNA undetectable on follow-up on Days 16 and 28. This is in contrast to placebo treated subjects who had a mean RSV RNA of 0.52 log₁₀ plaque forming unit equivalents (PFUe)/mL on the day of discharge. The viral load reduction in infected subjects across all dosing regimens was associated with concomitant improvements in RSV symptom scores and reductions in mucus weight.