Ark Biopharmaceutical has shared a closer look at the data it hopes will secure approval of its antiviral ziresovir in the treatment of respiratory syncytial virus (RSV), linking the candidate to significantly shorter intensive care stays and reduced wheezing in the months after treatment.
Shanghai-based ArkBio entered the RSV race in 2014 by striking a deal for ziresovir, a RSV fusion inhibitor that was discovered by Roche. The biotech guided the candidate through early and mid-phase trials, leading to the delivery of top-line data from a pivotal study in April. The data drop revealed the phase 3 trial of 311 infants hospitalized with RSV infection hit its primary endpoint, plus a secondary endpoint.
ArkBio recently repeated the top-line data at the International RSV Symposium, where it also revealed some figures that were excluded from its original release. The new data covers endpoints that could be important from payer and quality of life perspectives.
On the payer front, ArkBio now has evidence that ziresovir reduces the duration of expensive stays in ICUs. Among participants admitted to ICU, the average stay in the ziresovir arm was three days, compared to eight days in the placebo cohort. Linking ziresovir to shorter ICU stays could help ArkBio as it tries to show the pharmacoeconomic value of the therapy to payers and healthcare systems.
The latest ArkBio release lacks data on other endpoints with pharmacoeconomic importance. ArkBio originally listed frequency of ICU admission and length of hospital stay as secondary endpoints, although it deleted the latter measure from the ClinicalTrials.gov listing two months after completing the study. The latest release lacks data on either measure.
The other new efficacy result reported in the latest release covers the follow-up data that are now available. Over the follow-up period, the rate of wheezing was lower in a subpopulation of children aged under six months who took ziresovir in comparison to their peers on placebo. The difference, 9.0% versus 26.3%, was statistically significant. Wheezing isn’t listed as an endpoint on ClinicalTrials.gov.
Upon releasing the top-line data in April, ArkBio outlined plans to file for approval in China around the middle of the year. The latest release lacks an update on the regulatory submission plan.