Numax(R) Achieves Primary Endpoint In Preliminary Analysis of Data From Comparative Phase 3 Trial With Synagis(R)
Monday November 6, 7:15 am ET
- Numax Showed Non-Inferiority in Primary Endpoint with 26-Percent Relative Reduction in RSV Hospitalizations Among High-Risk Infants -
- Numax Also Showed Superiority Over Synagis for a Secondary Endpoint by Achieving a 52-Percent Relative Reduction in Incidence of Medically Attended Outpatient Lower Respiratory Infections Caused by RSV -
GAITHERSBURG, Md., Nov. 6 /PRNewswire-FirstCall/ -- MedImmune, Inc. (Nasdaq: MEDI - News) today announced preliminary results from a Phase 3 pivotal study showing that Numax met its primary endpoint of non-inferiority by reducing the incidence of hospitalizations caused by respiratory syncytial virus (RSV) in infants at high risk for serious RSV disease by 26 percent when compared to Synagis® (palivizumab). The data also indicate that Numax showed superiority over Synagis in a secondary endpoint by reducing the incidence of RSV-specific medically attended outpatient lower respiratory infections (LRI) by approximately 52 percent.
"We are very pleased with the outcome of this large, multi-national Phase 3 study comparing Numax to Synagis, which is the current standard of care in the U.S. for preventing RSV in high-risk infants," said Edward M. Connor, M.D., chief medical officer and executive vice president. "The preliminary results of this study are highly encouraging and indicate that Numax may have the potential to offer high-risk infants additional protection against RSV infection over and above Synagis, which has an established safety and efficacy profile. We intend to continue to evaluate the complete data set to more fully understand the trial results, and then to review the data with the U.S. Food and Drug Administration."
The pivotal Phase 3 study was designed to compare the safety and efficacy of Numax with that of Synagis in infants at high risk for serious RSV disease for the reduction of serious RSV disease in the inpatient and outpatient settings. The primary endpoint was to assess the non-inferiority of Numax compared to Synagis in the incidence of hospitalizations caused by RSV. By design, non-inferiority was defined to have been demonstrated if the upper bound of the two-sided 95 percent confidence interval of the relative risk (RR) for the primary endpoint was lower than 1.265. As indicated above, Numax showed a 26-percent reduction [RR: 0.737, 95 percent CI: (0.503, 1.083)] in RSV hospitalizations compared to Synagis. The corresponding p-value for non- inferiority analysis was < 0.01. In the trial, the overall RSV attack rate was 1.4 percent for infants receiving Numax compared to 1.9 percent for those who received Synagis. The study's RSV-related secondary efficacy endpoint, conducted in a subset of sites, was the comparative reduction of RSV-specific medically attended outpatient LRI. Numax showed a 52-percent statistically superior reduction in RSV-specific medically attended LRIs compared to Synagis; the overall RSV-specific medically attended LRI rate was 1.9 percent for infants receiving Numax compared to 3.9 percent for those who received Synagis (p = 0.003).
"The conduct of this trial by study investigators was outstanding," commented Genevieve Losonsky, M.D., vice president, clinical development, infectious disease. "The trial's success is a testimony to the quality of their work, as well as to the commitment of their staff and to the parents . on the part of their children who participated in the study."
In this preliminary assessment, the number and type of adverse events and serious adverse events were balanced between the study groups. The overall mortality rates were comparable between the two groups (0.1 percent Synagis and 0.2 percent Numax). Study drug was discontinued due to related adverse events in a small number of children in each group (0.1 percent Synagis and 0.3 percent Numax). Immunogenicity in the Numax arm was low, less than 1 percent, and comparable to the historical Synagis rate.
The trial was a randomized, double-blind study involving approximately 6,600 high-risk infants at more than 300 centers in 24 countries within the Northern and Southern Hemispheres conducted over two years during multiple RSV seasons. Study participants consisted of premature infants born at 35 weeks gestational age or less who were six months of age or younger at randomization, as well as children with chronic lung disease related to prematurity (CLD) requiring medical management within the six months prior to study entry, who were 24 months of age or less at randomization.
About RSV
Each year, an estimated 125,000 infants in the United States are hospitalized with severe RSV infections, the leading cause of infant hospitalization in the U.S.(1) RSV is the most common respiratory infection in infancy or childhood. Approximately one-half of all infants are infected with RSV during the first year of life, and nearly all children have been infected at least once by the time they reach their second birthday. Children born prematurely as well as those with chronic lung disease or congenital heart disease are at highest risk for severe disease and hospitalization due to RSV. The virus may also cause severe illness in other high-risk groups such as the elderly, those with underlying respiratory or cardiac disease, and those with compromised immune systems (e.g., bone marrow transplant patients).
About Numax
Numax is an investigational humanized monoclonal antibody being evaluated for its potential to prevent serious lower respiratory tract disease caused by RSV in pediatric patients at high risk of RSV disease. Phase 1 and Phase 2 studies have been reported showing that Numax appears to have a similar safety and pharmacokinetic profile to Synagis in infants. Additionally, in early phase studies children treated with Numax had reduced RSV replication in the upper respiratory tract. |
