University of Virginia Health System

PIVOTAL DATA ON POTENTIAL ANTIVIRAL TREATMENT FOR THE COMMON COLD FEATURED DURING PREMIER INFECTIOUS DISEASES CONFERENCE

The University of Virginia School of Medicine today announced that Dr. Frederick Hayden, professor of internal medicine and pathology, presented data during the 41st annual Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC), as part of a press conference held during the scientific meeting. The data represent the most recent clinical findings about pleconaril, a novel antiviral compound being developed for the treatment of viral respiratory infection (VRI), otherwise known as the common cold. The National Institutes of Health estimates that there are one billion colds annually in the United States. Currently, there are no antiviral treatments available that target the most common underlying cause of the cold, picornaviruses.

Picornaviruses account for approximately one-half of all colds and many other serious respiratory illnesses, including sinusitis, otitis media, and exacerbations of asthma and COPD, Hayden said. These are the first pivotal studies in which patients receiving a drug targeting the picornavirus experienced a reduction in the severity and duration of their colds.

Hayden's presentation, Pleconaril Treatment Reduces Duration and Severity of Viral Respiratory Infection (Common Cold) Due to Picornaviruses, included results from two randomized, double-blind, placebo-controlled Phase 3 studies evaluating the safety and efficacy of oral pleconaril in the treatment of common colds caused by picornaviruses in adults. The two studies enrolled a total of 2,096 adult patients who presented with cold symptoms including moderate or severe rhinorrhea (runny nose) and at least one other respiratory symptom.

Within 24 hours of the onset of symptoms, patients were randomized to receive pleconaril 400 mg three times per day or placebo for five days. Approximately two-thirds of the patients were found to have picornavirus infection as determined by polymerase chain reaction (PCR) testing of nasal mucus samples. The primary study outcome measure was the time to complete resolution of rhinorrhea with all other symptoms absent or mild for at least 48 hours.

Compared to placebo, patients treated with pleconaril experienced a one-day reduction in this study endpoint (integrated results from both studies: 6.3 days vs. 7.3 days, p<0.001). The time to reduction in VRI symptom severity to one-half of the baseline severity was also significantly reduced by greater than 25 percent in the pleconaril group compared to placebo (integrated results from both studies: 2.9 days vs. 3.9 days, p <0.001). Overall symptom severity was significantly reduced by pleconaril on the day after starting treatment and remained lower than placebo throughout the remainder of the treatment period.

Each of the individual VRI symptoms that were evaluated (rhinorrhea, nasal congestion, cough, sore throat, myalgia, and malaise) resolved significantly more rapidly in patients treated with pleconaril. In addition, pleconaril-treated patients reported significant reductions in nights with sleep disturbance (33 percent), use of cold medications (0 use vs.1 day with placebo) and use of facial tissues (24 percent) during the study. The antiviral activity of pleconaril was shown by a significant reduction in the percentage of patients with positive viral cultures from nasal mucus samples as early as the second day of treatment.

Pleconaril was well tolerated, and adverse events reported were comparable to placebo. The most frequently reported adverse events in both placebo and pleconaril groups were headache, diarrhea and nausea. In summary, the results from these studies showed that early treatment with pleconaril promptly and significantly reduced the duration and severity of picornavirus VRI symptoms in adults.

PICOVIR™ (pleconaril) has been studied in more than 4,000 patients, and is being co-developed and marketed by ViroPharma Incorporated of Exton, Pennsylvania, and Aventis Pharmaceuticals, headquartered in Bridgewater, New Jersey. Pleconaril is currently under review by the U.S. Food and Drug Administration (FDA).

Picornaviruses are small (pico means very small) RNA-containing (RNA means ribonucleic acid) viruses and represent one of the largest and most important groups of human pathogens. Rhinoviruses and enteroviruses, members of the picornavirus family, are closely related. Rhinoviruses infect principally the upper respiratory tract and are the single most important cause of the common cold.

December 17, 2001