Isis Announces Positive Phase 2 Data For ISIS-FXIRx

(RTTNews) - Isis Pharmaceuticals Inc (ISIS) on Sunday announced positive final data from its Phase 2 comparator-controlled study evaluating the incidence of venous thromboembolic events (VTE) in patients treated with ISIS-FXIRx undergoing total knee replacement surgery, or total knee arthroplasty (TKA). ISIS-FXIRx is designed to reduce the production of Factor XI, a coagulation factor that plays a key role in thrombosis.

These data were published in The New England Journal of Medicine and will be presented at the 56th American Society of Hematology meeting as a late-breaking oral presentation on December 9.

In the paper and presentation titled 'Factor XI Antisense Oligonucleotide for Prevention of Venous Thrombosis' the authors report that ISIS-FXIRx-treated patients experienced a dose-dependent decrease in venous thromboembolic events.

Patients treated with 300 mg of ISIS-FXIRx experienced a seven-fold lower rate of VTE as compared with those treated with enoxaparin (4.2% and 30.4%, respectively; p<0.001). Patients treated with 200 mg of ISIS-FXIRx had a rate of VTE comparable to that in patients treated with enoxaparin (26.9% and 30.4%, respectively).

The rate of VTE in patients given enoxaparin is within the range documented in previous studies in this therapeutic setting. ISIS-FXIRx treatment was associated with a dose-dependent and sustained reduction in Factor XI activity that correlated with the lower rate of VTE. The rate of bleeding was low with ISIS-FXIRx and enoxaparin.

Isis said its plan is to bring in a partner for later-stage development and commercialization of this program, and that it has already had considerable interest from potential partners.

The Phase 2 study of ISIS-FXIRx in 293 patients undergoing TKA was a global, multi-center, open-label, comparator-controlled study comparing ISIS-FXIRx with enoxaparin.

In this study, ISIS-FXIRx was well tolerated. There were no observed differences in safety outcomes compared with enoxaparin. In particular, there were no flu-like symptoms, and injection site reactions were infrequent and mild. There have been no drug-related serious adverse events reported to date.

The Phase 2 study was published ahead of print and on-line in The New England Journal of Medicine on Sunday, December 7.