On Thursday, the National Institutes of Health’s National Institute of Allergy and Infectious Diseases (NIAID) announced topline results from a preliminary analysis of the PALM 007 trial of tecovirimat for the treatment of monkeypox virus (mpox).

SIGA Technologies ( SIGA ) sells tecovirimat under Tpoxx, an antiviral medication against orthopoxviruses such as smallpox and mpox.

NIAID reported that the study did not meet its primary endpoint of a statistically significant improvement in time to lesion resolution within 28 days post-randomization for patients in the Democratic Republic of the Congo with mpox who were administered SIGA’s tecovirimat versus placebo.

Also Read: WHO Declares Mpox Public Health Emergency: ‘Coordinated International Response Essential’ To Halt Outbreak.

All patients in this study were hospitalized for the entire duration of treatment.

This study was not a registration study conducted under an FDA Investigational New Drug Application.

A meaningful improvement was observed in patients receiving tecovirimat whose symptoms began seven days or fewer before randomization and those with severe disease.

“We believe these data warrant further investigation and support our view that post-exposure prophylaxis will be vital for treatment of severe cases of mpox and all cases of smallpox,” stated Dennis Hruby, Chief Scientific Officer.

Additionally, in this study, tecovirimat exhibited a safety profile comparable to that of the placebo.

These results are consistent with several prior studies in healthy volunteers and further support the strong safety profile observed with tecovirimat over the past 15 years.

The PALM 007 study was part of a globally coordinated initiative to address the 2022 mpox outbreak in the DRC and worldwide.

In PALM 007, patients in the placebo arm had much more favorable outcomes than those in the observational studies from the DRC that were used to plan this trial, which could have reduced the measured benefit of tecovirimat compared to placebo.

The exact impact of this controlled environment on the trial results is not yet known.

However, the study’s 1.7% overall mortality among enrollees, regardless of whether they received the drug or not, was much lower than the mpox mortality of 3.6% or higher reported among all cases in the DRC.

This shows that patients with mpox can achieve better outcomes when hospitalized and receive high-quality supportive care.

Price Action: SIGA ( SIGA ) stock is down 38.3% at $7.39 during the premarket session at last check Thursday.