October 13, 2014 08:30 ET

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

AL-8176 Treatment Rapidly Achieved Non-Detectability of RSV RNA and Decreased Clinical Symptoms

SOUTH SAN FRANCISCO, CA--(Marketwired - Oct 13, 2014) - Alios BioPharma, Inc. presented results from a randomized, double-blind, placebo-controlled Phase 2 challenge study of its oral anti-RSV nucleoside analog AL-8176 this past weekend at the IDWeek 2014 Conference in Philadelphia, PA. 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 < 0.05) as compared to placebo. AL-8176 was well tolerated with no discontinuations of study drug and no clinically significant laboratory abnormalities.

In successfully infected subjects, a rapid and marked reduction in RSV viral load was observed following treatment in all three AL-8176 treated dose groups as compared to placebo. In contrast, successfully infected placebo subjects exhibited a logarithmic increase in RSV RNA with a peak viral load at Day 3.5 following start of dosing with placebo. The mean time to non-detectability of RSV RNA was 1.3-2.3 days for the AL-8176 treatment groups compared to 7.2 days in the placebo group. At discharge (Day 12), all subjects treated with AL-8176 were RSV RNA undetectable and remained RSV RNA undetectable upon follow-up on Days 16 and 28. The viral load reduction in infected subjects across all AL-8176 dosing regimens was associated with concomitant improvements in RSV symptom scores and reductions in mucus weight. 

The Alios study enrolled 62 healthy adult volunteers between the ages of 18 - 45 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 or placebo was initiated 12 hours after confirmation of RSV infection as determined by presence of RSV RNA in nasopharyngeal washes. Thirty-five of the 62 patients met the criterion for infection (ITT-I population). 

The data was presented by John DeVincenzo, MD, Professor of Pediatrics and Professor of Microbiology, Immunology and Biochemistry at the University of Tennessee School of Medicine, as part of a late-breaker session on Saturday, October 11 at the IDWeek 2014 meeting. "These positive data represent a validation of the potent antiviral effects of an RSV replication inhibitor and further demonstrate the progress that Alios has made towards developing a therapy for RSV infections, a disease which affects millions of children in the US and untold more worldwide," stated Dr. DeVincenzo. "The ongoing trial assessing the impact of AL-8176 in infants with RSV is an important next step and will be the first opportunity to assess efficacy and safety of AL-8176 directly in those who need it most."

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 sixth 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 have been 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 show 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, Inc. is a clinical stage biopharmaceutical company in South San Francisco, CA that is developing novel therapies for the treatment of viral 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, coronavirus and hepatitis C. On September 30, 2014, Johnson & Johnson (NYSE: JNJ) announced a definitive agreement to acquire Alios for approximately $1.75 billion in cash. The transaction is expected to close in the fourth quarter of 2014. For more information please visit

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