A combination of recombinant interferon beta-1b and lopinavir–ritonavir reduced mortality in patients with Middle East respiratory syndrome (MERS) compared to placebo, according to a study published in the New England Journal of Medicine. Treatment was most successful when started within the first 7 days of symptom onset.
In this a randomized, adaptive, double-blind, placebo-controlled trial, 95 patients with MERS were randomly assigned to receive recombinant interferon beta-1b plus lopinavir–ritonavir (intervention, n = 53) or placebo (n = 52) for 14 days. The primary outcome was 90-day all-cause mortality, with a one-sided P-value threshold of 0.025.
By day 90, 28% of patients (n = 12) in the intervention group and 44% (n = 23) in the placebo group had died. After accounting for the adaptive design, the primary outcome analysis yielded a risk difference of −19 percentage points (upper boundary of the 97.5% confidence interval [CI], −3; one-sided P = 0.024).
A prespecified subgroup analysis found that when treatment was started within 7 days of symptom onset, 90-day mortality was lower than the use of placebo (relative risk, 0.19; 95% CI, 0.05 to 0.75), but was not when treatment was started later.
Serious adverse events occurred in 9% (n = 4) in the intervention group and in 19% (n = 10) in the placebo group.