Update on Phase 2b clinical study of lead asset XF-73 in the prevention of post-surgical bacterial infections

Protocol amendment agreed with FDA to reduce Phase 2b study size without compromising its statistical power or clinical value

Study two thirds enrolled. Recruitment now expected to complete by year end

Planned study interim safety review to be announced in August 2020

Brighton, United Kingdom – 27 July 2020 – Destiny Pharma plc (AIM: DEST), a clinical stage biotechnology company focused on the development of novel treatments for hospital infections that address the global challenge of antimicrobial resistance (AMR), is pleased to announce a clinical protocol amendment has been agreed with FDA for its ongoing phase 2b study of lead asset XF-73.

The study is evaluating XF-73, as a nasal gel, for the prevention of post-surgical hospital infections caused by Staphylococcus aureus bacteria, such as MRSA. The agreed amendment recognizes the impact COVID-19 has had in slowing patient recruitment in clinical studies since March and the FDA’s willingness to support certain protocol amendments that help to accelerate the completion of ongoing clinical trials but do not compromise a study’s integrity and clinical objectives.

The amendment to the protocol incorporates a change to the primary patient population where the primary endpoint for the study will be measured. The primary microbiological endpoint post-surgery will now be measured in those patients who had a positive load of nasal Staphylococcus aureus before receiving the study treatment. This contrasts to the original primary population, which included all randomised patients regardless of their baseline nasal load of Staphylococcus aureus. Very importantly, this change enables a reduction in the prospectively defined study size from 200 patients to 125 while maintaining the statistical power of the study and its clinical value. This preserves the potential of the trial results to be a key step towards the Phase 3 clinical trial programme of XF-73. Destiny Pharma has informed all appropriate regulatory bodies and ethics committees involved. Other protocol modifications agreed with the FDA regarding study procedures will also make it easier for hospitals to recruit and retain hospital patients.

Destiny Pharma expects that as the incidence of COVID-19 continues to decline in European hospitals they will begin recruiting patients into the study again and that recruitment into US study sites is likely to lag, given the higher infection incidence. That said, the study has already enrolled 77 patients out of the new target of 125 and the Company expects to have over 20 sites open in three countries actively recruiting the remaining patients in the next few months with the majority of these being FDA-compliant sites in Europe. The study remains on track to complete recruitment by the end of 2020. The result of a planned interim safety review by the study’s Independent Safety Monitoring Board is expected to be announced in August 2020.

Neil Clark, Chief Executive Officer of Destiny Pharma, commented:

“We are very pleased to have agreed the protocol amendment with the FDA. The changes will help us complete recruitment later in 2020 and still be well placed to move towards Phase 3 clinical studies if the Phase 2b results are positive. Destiny Pharma is funded through to the last quarter of 2021 and remains confident in the clinical need and significant commercial opportunity for its lead clinical asset XF-73 as a novel preventive treatment of serious hospital infections”.