Adamas Pharmaceuticals presents study results of TCAD therapy in immunocompromised influenza A patients

Adamas Pharmaceuticals, Inc., a privately held company, announced today the results from the first clinical study evaluating triple combination antiviral drug (TCAD) therapy for the treatment of influenza A in immunocompromised patients.  Data from this Phase 1b study were presented by clinical investigator Dr. Janet Englund in a clinical symposium at the 23rd International Conference on Antiviral Research (ICAR) in San Francisco.

"This pilot study was an important first step in validating that the combination of three antivirals can provide a virologic and clinical benefit to patients at risk for complications of influenza," said Janet Englund, M.D., Professor of Pediatrics, Seattle Children's Hospital and Clinical Associate, Fred Hutchinson Cancer Research Center, Seattle, Washington.  "These findings warrant continued investigation of TCAD as a potentially broad spectrum treatment to address drug resistant influenza."

During treatment of patients with severe influenza or at risk for complications, mounting evidence suggests that the use of antivirals as monotherapy results in the emergence of strains resistant to both classes of approved drugs, creating a pressing need for new combination influenza therapies.  

The study conducted by investigators at the Fred Hutchinson Cancer Research Center in Seattle, Washington, and Seattle Children's Hospital, was a randomized, open-label study of TCAD therapy (amantadine and ribavirin administered with oseltamivir) versus oseltamivir monotherapy in immunocompromised patients with Influenza A.  The objective of the study was to assess the safety, tolerability, and virologic benefit of oral TCAD therapy.  A total of seven patients with confirmed influenza A were enrolled.  Data from the study demonstrated that up to 10 days of TCAD therapy was observed to be well tolerated, with five of six TCAD-treated subjects who completed the study achieving a clinical response by day 10.  In contrast, the single patient in the oseltamivir monotherapy treatment arm did not respond to 20 days of treatment.  Importantly, this patient developed an oseltamivir resistant strain by day seven that persisted to the end of treatment, resulting in the shedding of a multidrug resistant (MDR) strain of influenza.

"These results represent the first report of triple combination therapy in human clinical studies of influenza," said Gregory T. Went, Ph.D., Chairman and Chief Executive Officer of Adamas.  "We are committed to developing a broad spectrum therapy to fill a significant gap in healthcare, specifically, an influenza drug treatment that remains active during a full course of therapy, and reduces the risk of multidrug resistance."