AL-8176 Significantly Reduced Viral Load to Undetectable Levels and Decreased Clinical Symptoms

SOUTH SAN FRANCISCO, CA, USA I July 23, 2014 I 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

“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. 

“This is the first demonstration of potent antiviral effects for an RSV replication inhibitor and is an important milestone for patients suffering from this serious infection,” stated Lawrence M. Blatt, PhD, President and Chief Executive Officer. “The positive data from this Phase 2 study for the treatment of RSV further demonstrates the progress that Alios has made toward our goal to develop therapies that address major respiratory viral infections where there are no effective treatment options.”

About the RSV Human Challenge Study
The study was conducted at Retroscreen Virology’s viral challenge unit in London, UK. The study utilized an adaptive design, enrolling up to 22 patients per quarantine, with a total of 62 patients enrolled across 3 quarantine periods. The patients were dosed twice daily (BID) for five days approximately 12 hours after subjects had a documented RSV infection (confirmed by PCR) or from the 6th day after receiving the RSV challenge (whichever came first). 

About Respiratory Syncytial Virus (RSV)
RSV is a negative-sense, single-stranded RNA virus from the Paramyxoviridae family and is associated with significant morbidity in the US and mortality in the developing world. RSV is the most common cause of serious lower respiratory tract infections in infants, and is an important cause of lower respiratory tract infections in the immunocompromised and in adults with chronic pulmonary diseases such as asthma and COPD. As many as 68% of infants are infected during their first RSV season and nearly 100% of children contract the virus by their second or third year. Currently, there are no effective therapeutics available for treating RSV, limiting treatment to supportive care. RSV infections are also linked to later development of asthma in children. 

About AL-8176
AL-8176 is a nucleoside analog which is being developed by Alios BioPharma as an orally administered antiviral therapy for the treatment of infants infected with RSV. AL-8176 is designed to inhibit the replication of the RSV by acting on the viral polymerase. In vitro studies of the compound showed potent and highly selective inhibition of both RSV laboratory-adapted A and B strains as well as a range of diverse clinical isolates. Similar to other nucleoside analogs, AL-8176 demonstrates a high barrier to the development of viral resistance. 

About Alios BioPharma
Alios BioPharma is a clinical stage biopharmaceutical company in South San Francisco, CA that is developing novel antiviral therapies for the treatment of respiratory diseases. The Alios virology discovery and development platform consists of a proprietary chemical library of nucleoside analogs as well as novel, proprietary virology-based screening systems. Alios is developing a portfolio of potential therapeutics for viral infections including respiratory syncytial virus (RSV), influenza, rhinovirus and coronavirus. For more information please visit www.aliosbiopharma.com.

SOURCE: Alios BioPharma