Company Announcements

hVIVO plc

("hVIVO" or the "Company")

Positive results from influenza human challenge study conducted by hVIVO

Pneumagen to advance antiviral candidate into further clinical studies

hVIVO plc (AIM & Euronext: HVO), the world leader in testing infectious and respiratory disease products using human challenge clinical trials, notes the announcement by Pneumagen, a clinical-stage biotech company, reporting successful clinical proof of concept for its broad-spectrum antiviral candidate Neumifil, demonstrated from a Phase 2a influenza human challenge study conducted by hVIVO.

The randomised, double-blind, placebo-controlled study enrolled 104 healthy adult volunteers, recruited through the FluCamp platform, and evaluated two dose regimens of Neumifil, administered as an intranasal spray to participants who were subsequently infected with influenza virus.

Based on these positive clinical results, taken together with a pre-clinical data package demonstrating Neumifil's activity against a broad range of viruses, Pneumagen now plans to advance Neumifil into further clinical studies. This will include the evaluation of Neumifil's ability to reduce the incidence of viral induced exacerbations in patients with Chronic Obstructive Pulmonary Disease ("COPD").

Neumifil demonstrated a clinically significant reduction in the incidence of symptomatic influenza infection and in the severity of symptoms, which achieved statistical significance compared to placebo. Neumifil was well tolerated with no new emergent adverse events or safety signals from the study compared to its first in human study.

Dr Andrew Catchpole, Chief Scientific Officer of hVIVO, said: "We are delighted to see Pneumagen obtain these results clearly achieving clinical proof of concept for Neumifil, which has supported Pneumogen's decision to progress the candidate into further clinical studies, including in patients with COPD. This is another example of the value of human challenge trials in delivering clinical efficacy data and de-risking later clinical development."

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Notes to Editors

About hVIVO

hVIVO plc (ticker: HVO) (formerly Open Orphan plc) is a rapidly growing specialist contract research organisation (CRO) and the world leader in testing infectious and respiratory disease vaccines and therapeutics using human challenge clinical trials. The Group provides end-to-end early clinical development services to its large, established and growing repeat client base, which includes four of the top 10 largest global biopharma companies.

The Group's fast-growing services business includes a unique portfolio of 11 human challenge models, with a number of new models under development, to test a broad range of infectious and respiratory disease products. The Company has world class challenge agent manufacturing, specialist drug development and clinical consultancy services via its Venn Life Sciences brand, and a lab offering via its hLAB brand, which includes virology, immunology biomarker and molecular testing. The Group offers additional clinical field trial services such as patient recruitment and clinical trial site services.

hVIVO runs challenge studies in London from its Whitechapel quarantine clinic, its state-of-the-art QMB clinic with its highly specialised on-site virology and immunology laboratory, and its clinic in Plumbers Row. To recruit volunteers / patients for its studies, the Company leverages its unique clinical trial recruitment capability via its FluCamp volunteer screening facilities in London and Manchester.