Petrovax announced today the positive results from “Long-CoV-III-21,” a randomized, double-blind, placebo-controlled trial evaluating the efficacy and safety of bovhyaluronidase azoximer in adult patients with pulmonary sequelae of COVID-19. Bovhyaluronidase azoximer, marketed under the brand name Longidaza, is a polymer-conjugated hyaluronidase with an extended half-life. The study drug and placebo were administered for 71 days, with an observation period extending to Day 180.

Longidaza demonstrated a statistically significant 62% reduction in the proportion of patients with exertional desaturation (OR = 0.35, p = 0.0051) and a 27% reduction in the proportion of patients exhibiting exertional dyspnea (OR = 0.62, p = 0.043) by Day 71 compared to placebo. Marked improvements were also observed in resting dyspnea and distance walked during the six-minute walk test. The drug’s effects on exercise tolerance indicators were sustained for more than 100 days after the last dose.

Longidaza did not affect pulmonary function in the overall population. However, subgroup analysis revealed that the drug was associated with a significantly greater change from baseline in predicted Forced Vital Capacity (FVC) in patients with cardiovascular comorbidities (difference = 3.31%, p = 0.042) and in those infected with earlier variants of SARS-CoV-2 (difference = 4.17%, p = 0.021) compared to placebo.

Long-CoV-III-21 is among the first randomized, double-blind trials to show a significant effect of a novel therapy in patients with post-COVID pulmonary sequelae. The sustained effects of Longidaza offer hope for patients struggling with dyspnea, fatigue, and reduced physical capacity to improve their quality of life. Although the drug did not show a significant effect on pulmonary function recovery in the entire study population, results in subgroups strongly suggest that research into hyaluronidase-based medications should continue-;not only for post-COVID pulmonary sequelae but also for other fibrotic conditions.”

Sergey Avdeev, MD, Chair of the Pulmonology Department at Sechenov University and principal investigator of the trial

Study findings were presented at the Asian Pacific Society of Respirology congress in Hong Kong.

In parallel with long COVID research, Petrovax has been developing an inhaled form of Longidaza for the treatment of interstitial lung diseases. The safety of this new delivery route was demonstrated in a recent Phase 1 study. A Phase 2 trial of inhaled Longidaza in patients with idiopathic pulmonary fibrosis is planned for 2025.

About Long-CoV-III-21

Long-CoV-III-21 is a prospective, randomized, double-blind, placebo-controlled clinical trial designed to test the efficacy and safety of Longidaza (3000U) intramuscular injections in patients with pulmonary sequelae of COVID-19 (NCT06383819). Three hundred ninety-two patients were randomized 1:1 to receive either Longidaza or placebo every 5 days for 71 days. The follow-up period lasted up to Day 180. The study enrolled patients with a history of COVID-19 infection 1 to 12 months prior to screening, restrictive lung disease, fibrotic-like radiological abnormalities in the lungs, and decreased SpO2 at rest or after exertion. The study was conducted at 37 clinical sites.

The primary endpoint was the change from baseline in predicted Forced Vital Capacity.

The main secondary endpoints included the proportions of patients with exertional desaturation and dyspnea after the six-minute walk test, the distance walked in the six-minute walk test, and dyspnea at rest.