Amplyx Pharmaceuticals, a biotech company developing innovative therapies for debilitating and life-threatening diseases in patients with compromised immune systems, today announced that it has closed a $53 million Series C extension, which brings the Series C round to over $90 million. The financing was led by Sofinnova Investments, with participation from existing investors including New Enterprise Associates, Lundbeckfonden Ventures, Arix Bioscience, Pappas Capital, RiverVest Venture Partners, 3Ã-5 Partners and BioMed Ventures. New equity investment from Pfizer Inc. (NYSE: PFE) and Adage Capital Management completed the financing round. Amplyx will use the proceeds of the financing to advance the clinical development of the company's product candidates, fosmanogepix and MAU868.

"The current pandemic highlights the continued need for the development of safe and effective antimicrobial agents able to address emerging threats. This impressive syndicate of investors shares Amplyx's commitment to bringing life-saving, innovative medicines to patients with compromised immune systems," said Ciara Kennedy, Ph.D., president and chief executive officer of Amplyx. "This financing enables us to build on positive initial data for our lead program, fosmanogepix, in invasive candidemia, and expand to proof of concept studies in other invasive and difficult-to-treat fungal infections, including invasive aspergillosis. In addition, we continue to advance MAU868, our monoclonal antibody, for the treatment of clinically significant BKV infection in people who have received either a kidney or hematopoietic cell transplant."

Annaliesa Anderson, Ph.D., FAAM, vice president and chief scientific officer, bacterial vaccines and hospital, Pfizer, added, "It is important that the growing threat of current and emerging treatment-resistant fungal pathogens is met by research and development efforts that deliver new treatment options for patients with invasive fungal infections. We look forward to supporting Amplyx as they work to develop therapies with a novel approach."

About Fosmanogepix
Fosmanogepix is a novel broad-spectrum antifungal agent being evaluated in clinical trials in patients with life-threatening fungal infections. Enrollment was recently completed in a Phase 2 trial evaluating the safety and efficacy of the intravenous and oral formulations of fosmanogepix for the treatment of patients with Candida infections. In that study, fosmanogepix demonstrated a high level of treatment success in the first 10 patients treated. Additional Phase 2 studies of fosmanogepix are ongoing in patients with Aspergillus and other mold infections, as well as infections caused by multi-drug-resistant Candida auris, a life-threatening fungal infection recently characterized as an "urgent" threat by the Centers for Disease Control.

Fosmanogepix has a novel mechanism of action, and its active moiety has shown broad-spectrum activity against common species of Candida and Aspergillus, including multi-drug- resistant strains such as C. auris and C. glabrata, as well as rare hard-to-treat molds including Fusarium, Scedosporium and some fungi from the Mucorales order. Invasive fungal infections result in high mortality rates (30-80%) despite standard-of-care treatment. The frequency of fungi resistant to both the azole and echinocandin classes of drugs is increasing and there is a significant unmet medical need for a new broad-spectrum antifungal.

Fosmanogepix has received Fast Track and Orphan Drug designations from the U.S. Food and Drug Administration for seven separate indications, and is designated as a Qualified Infectious Disease Product (QIDP) for the treatment of four indications.

About MAU868
MAU868, a potent neutralizing monoclonal antibody with activity against BK virus (BKV), is entering Phase 2 development for the prevention or treatment of devastating and often life-threatening diseases associated with BKV infection in transplant patients. MAU868 neutralizes all four genotypes of BKV at sub-nanomolar concentrations and has a high barrier to resistance in vitro.

Reactivation of BKV, which is present and usually remains latent in 80 to 90% of the population, can occur following immunosuppression in patients who have undergone kidney or hematopoietic cell transplantation. BKV disease can lead to devastating and costly consequences, such as nephropathy and rejection that primarily affect kidney transplant recipients, and hemorrhagic cystitis that affects hematopoietic cell transplant recipients.

About Amplyx Pharmaceuticals
Amplyx Pharmaceuticals is developing innovative therapies for patients with compromised immune systems, including cancer and transplant patients, and the critically ill. The company's two lead products are fosmanogepix (APX001), for the treatment of life-threatening fungal infections caused by pathogens such as Candida, Aspergillus and rare molds, and MAU868, a monoclonal antibody that potently neutralizes the BK virus, which can cause significant morbidity and mortality in transplant patients. For more information, please visit www.amplyx.com