For Isis, the positive data resulted from its Phase 2 comparator-controlled study of ISIS-FXIRx, which inhibits the production of Factor ZI, a coagulation factor linked to thrombosis. The study sought to evaluate the incidence of venous thrombolic events (VTEs) in patients treated with the compound undergoing either total knee replacement surgery or total knee arthroplasty (TKA), comparing both the activity and safety of ISIS-FXIRx with that of enoxaparin. Patients treated with ISIS-FXIRx saw a dose-dependent decrease in VTEs. Those patients who were treated with both ISIS-FXIRx enoxaparin experience a low rate of bleeding, with ISIS-FXIRx-treated patients seeing fewer bleeding events compared to the patients receiving enoxaparin.

 

ISIS-FXIRx proved to be well tolerated by the study participants, with no observed differences in safety compared to the patients receiving enoxaparin. No drug-related serious adverse reactions have been reported to-date, and injection-site reactions were infrequent and mild.

 

“Genetic and preclinical studies clearly suggest that reducing Factor XI should be a more effective means of reducing thrombogenic events than reducing other coagulation factors, and could be associated with very low bleeding risk. In fact, in head-to-head comparisons in animal models, we have shown that inhibiting Factor XI was more effective and produced less bleeding than achieved with warfarin or Factor Xa inhibitors. The results from this Phase 2 study support this attractive profile,” Dr. Brett Monia, senior vice president of antisense drug discovery at Isis, said in a press release.

 

“TKA results in a high incidence of VTEs,” he continued. “By evaluating our drug in this therapeutic setting, we have been able to directly compare the activity and safety of ISIS-FXIRx to enoxaparin, a commonly prescribed anticoagulant. These data suggest that ISIS-FXIRx has a low bleeding risk and is a more effective antithrombotic agent than enoxaparin. Given the mechanism of Factor XI inhibition, we believe that this drug could be used broadly to prevent VTE in many different therapeutic settings as well as other therapeutic indications requiring safe and effective thromboprophylaxis. We believe based on this robust data package that ISIS-FXIRx represents a significant licensing opportunity.”

 

For its part, Gilead Sciences, Inc. reported that GS-5806, an investigational oral respiratory syncytial virus (RSV) fusion inhibitor, successfully achieved its lead endpoints in a Phase 2a challenge study. The primary and secondary endpoints consisted of lower viral load, improvements in total mucus weight and symptom diary score compared to placebo. No serious adverse events were witnessed in the study, with all adverse events registered as either mild or moderate in severity, with the exception of one placebo patient. The only treatment-emergent adverse event reported by two or more patients in either group was Grade 1 pulmonary function decrease.

 

The RSV pathogen infects the respiratory tract, which can lead to brochiolitis and pneumonia, with an increased risk of severe disease and death in premature infants, individuals with some pulmonary diseases, immunosuppressed individuals and the elderly.

 

Gilead is not the only company hoping to get a successful RSV treatment to market; as noted in an article in our May issue (check out “Toward the first vaccine for a common infection”), CEVEC Pharmaceuticals has seen success in using CAP cells, an immortalized cell line, to produce RSV in a form with high potential for use in a vaccine.