149. Efficacy of Cochleated Amphotericin B (CAMB) in Mouse and Human Mucocutaneous Candidiasis

BACKGROUND: Candida albicans causes debilitating mucosal infections in patients with inherited susceptibility to chronic mucocutaneous candidiasis (CMC), often requiring long-term azole-based treatment. Due to increasing azole resistance, alternative treatments are desirable. Acquired resistance to amphotericin B (AMB) is rare but AMB use is limited by parenteral administration and nephrotoxicity. Cochleated AMB (CAMB) is a new oral formulation of AMB and thus an attractive option for oropharyngeal candidiasis (OPC), esophageal candidiasis (EC) and vulvovaginal candidiasis (VVC). We assessed the efficacy of CAMB in mouse models of OPC and VVC and in 4 patients with azole resistant CMC manifesting as OPC, EC or VVC. METHODS: Act1 (-/-) mice were infected with C. albicans in models of OPC and VVC and were treated once daily via oral gavage with CAMB or vehicle or intraperitoneal AMB-deoxycholate (AMBd) from day 1 through 4 post-infection (pi). At day 5 pi, the tongue or vaginal tissue was harvested to quantify fungal burden. Patients with azole resistant CMC enrolled in a phase 2A CAMB dose escalation study. The primary endpoint was clinical improvement at 2 weeks based on an efficacy scale, followed by optional extension for long-term suppression of CMC to assess safety and efficacy. RESULTS: CAMB-treated mice had significantly reduced tongue and vaginal tissue fungal burden compared to vehicle-treated mice, while they exhibited comparable fungal control relative to AMBd-treated mice. Among 4 CAMB-treated patients, 3 reached clinical efficacy by 2 weeks at a dose of 400 mg twice daily and one reached clinical efficacy at 200 mg twice daily. Three of 4 patients continued on the extension phase past 48 months with sustained clinical improvement of OPC and EC; patient #3 had relapse of esophageal symptoms at week 24 and was withdrawn from further study. Clinical response was not seen for onychomycosis or VVC. CAMB was safe and well-tolerated without renal toxicity. CONCLUSION: Oral administration of CAMB in IL-17-signaling deficient mice resulted in reduced tongue and vaginal tissue fungal burden during mucosal C. albicans infections. A proof-of-concept clinical trial in humans with inherited CMC showed efficacy in OPC and EC with good tolerability and safety. DISCLOSURES: Benjamin Colton, PharmD, Merck (Shareholder)Pfizer (Shareholder) Ruying Lu, n/a, Matinas BioPharma Inc. (Employee)Matinas BioPharma Inc. (Employee, Shareholder) Theresa Matkovits, PhD, Matinas BioPharma (Employee, Shareholder) Raphael J. Mannino, n/a, Matinas BioPharma Inc. (Employee, Shareholder) Michail Lionakis, MD, ScD, Matinas BioPharma (Research Grant or Support)