The Synairgen share price crashes again as US study is halted

Synairgen’s share price has slumped once more following fresh bad news for its SNG001 asset. Here’s what we need to know.

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The Synairgen (LSE: SNG) share price plunged following news that a US study involving its key SNG001 asset has been halted. The healthcare stock is down 17% in Thursday business.

It announced that the US National Institute of Allergy and Infectious Diseases (NIAID) — part of the National Institutes of Health (NIH) — has ceased patient recruitment for a phase II/III trial titled Protocol ACTIV-2/A5401. The study included the testing of SNG001. This is an inhalable formulation which contains the broad-spectrum antiviral protein interferon beta.

Synairgen said that trials have been halted “due to the significant shift in the nature of the pandemic”. This would require “a substantial modification of the study design not feasible in this multiple treatment-arm, platform trial.”

New trials needed

Synairgen said a new clinical trial design is now needed to test the efficacy of SNG001 against Covid-19. It added that “ongoing discussions” are now taking place between lead investigators from ACTIV-2 and Synairgen. This is “to try to identify an appropriate clinical trial to continue the evaluation of SNG001.”

Chief executive Richard Marsden added that the firm is “actively seeking inclusion in platform trials for hospitalised patients”. And it’s  “working closely with the NIH to also find a suitable trial for SNG001 in home-based patients.”

In February 2021, SNG001 had been included in the study on non-hospitalised adults experiencing mild to moderate Covid-19. The Synairgen share price has now fallen 88% since disappointing SNG001 trial data was released in mid-February.

Royston Wild has no position in any of the shares mentioned. The Motley Fool UK has no position in any of the shares mentioned. Views expressed on the companies mentioned in this article are those of the writer and therefore may differ from the official recommendations we make in our subscription services such as Share Advisor, Hidden Winners and Pro. Here at The Motley Fool we believe that considering a diverse range of insights makes us better investors.

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