Complete Results of our ALN-RSV01 Phase IIb Study

Complete Results of our ALN-RSV01 Phase IIb Study

At the European Respiratory Society’s (ERS) Annual Congress held in Vienna September 1-5, 2012, we presented complete results from our Phase IIb trial with ALN-RSV01 for the treatment of respiratory syncytial virus (RSV) infection in lung transplant patients…

The primary endpoint of the study was the incidence of new or progressive bronchiolitis obliterans syndrome (BOS) at 180 days after RSV infection.  In May 2012, we reported top-line results from this trial where we showed that although the study missed the primary endpoint of reduced BOS in an “intent-to-treat” (ITTc) analysis of confirmed RSV infected patients (p=0.058), it achieved statistically significant reductions  in prospectively defined analyses of ITTc patients with their “last observation carried forward” (LOCF) with a p-value of 0.028, and of ITTc patients treated “per protocol” (PP) with a p-value of 0.025.  In all analyses, ALN-RSV01 treatment was associated with a clinically meaningful treatment effect, with a reduction of over 50% in the incidence of day 180 BOS as compared with placebo.

New data presented at ERS included results from key secondary endpoints and certain post-hoc analyses, including results of a multivariate logistic regression analysis where treatment with ALN-RSV01 showed an over eight-fold reduced risk in developing day 180 BOS.  Further, we showed a statistically significant effect on the secondary endpoint of day 90 BOS, and demonstrated a particularly strong effect of over 80% in patients receiving ALN-RSV01 within five days of symptom onset.  In aggregate, results of secondary endpoints and additional post-hoc analyses continue to support the conclusion that treatment of RSV-infected lung transplant patients with ALN-RSV01 was generally safe and well tolerated and associated with a decreased incidence of new or progressive BOS.


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