Mundipharma Announces Further Phase III ReSPECT Results Presented as a Late-Breaking Oral Presentation at IDWeek 2026

CAMBRIDGE, England — Today Mundipharma announced additional results from the global Phase III ReSPECT clinical trial evaluating REZZAYO^® (rezafungin acetate) for prophylaxis of invasive fungal diseases (IFDs) in adult patients undergoing allogeneic haematopoietic stem cell transplantation (allo-HSCT). The Phase III findings were presented today as a late-breaking oral presentation at IDWeek 2026.

The presentation provides additional detail following the top line ReSPECT results announced in April 2026, including further endpoint analyses, the components contributing to fungal-free survival (FFS), pre-specified sensitivity analyses and detailed safety outcomes. The additional analyses were consistent with the previously announced topline findings.

ReSPECT was a global, multicentre, randomised, double-blind Phase III study in which 402 patients were randomised to rezafungin and 200 to the standard antimicrobial regimen. As previously announced, the study met its primary endpoint, demonstrating non-inferiority of rezafungin to the standard antimicrobial regimen for FFS at Day 90 following allo-HSCT.

The primary endpoint result was supported by six pre-specified sensitivity analyses examining the handling of indeterminate outcomes, definitions of IFD, randomisation stratification factors and the use of non-study systemic antifungal therapy.

• Phase III findings were presented as a late-breaking oral presentation at IDWeek 2026
• FFS at Day 90 was 60.7% with rezafungin and 59.0% with the standard antimicrobial regimen, corresponding to an estimated treatment difference of 1.6% (95% CI -6.2 to 9.3; P=0.0002 for non-inferiority)
• Proven or probable IFD contributing to FFS failure occurred in 3.5% of patients receiving rezafungin versus 4.5% receiving the standard antimicrobial regimen
• Data from ReSPECT have been submitted to the US Food and Drug Administration (FDA) and European Medicines Agency (EMA) for regulatory review

Antifungal prophylaxis is an important component of care for patients undergoing allo-HSCT, who are at risk of life-threatening IFD. Despite established prophylactic approaches, clinical challenges can include drug toxicities, drug–drug interactions, therapeutic drug monitoring, antifungal resistance and difficulties with daily oral administration, (including adherence to antimicrobial regimens). There remains an unmet need for continued research and evidence generation to optimise prevention in this complex, immunocompromised and medically vulnerable population.²Additional findings from ReSPECT The composite FFS endpoint incorporated survival, absence of proven or probable IFD as assessed by an independent Data Review Committee, and no use of non-study systemic antifungal therapy for more than 10 cumulative days.

Proven or probable IFD contributing to FFS failure occurred in 3.5% of patients receiving rezafungin and 4.5% receiving the standard antimicrobial regimen. Death contributing to FFS failure occurred in 4.5% and 5.5%, respectively, while use of non-study systemic antifungal therapy for more than 10 cumulative days was numerically lower in the rezafungin group, occurring in 27.4% and 32.5%, respectively.

The study also reported IFD caused by individual fungal species. Candida infections occurred in 1.2% versus 1.0%, Aspergillus infections in 2.0% versus 3.0%, and Pneumocystis jirovecii infections in 0.2% versus 0% in the rezafungin and standard antimicrobial regimen groups, respectively.

Treatment-emergent adverse events were reported in 99.7% of patients receiving rezafungin and 100% receiving the standard antimicrobial regimen. Serious adverse events occurred in 66.0% and 67.5% of patients, respectively. Treatment-emergent adverse events leading to study discontinuation occurred in 9.3% and 14.7%, while those leading to dose reduction, interruption or withdrawal of study treatment occurred in 31.0% and 47.7%, respectively. No new safety signals were identified in allo- HSCT recipients.

said Johan Maertens, MD, PhD, University Hospitals Leuven.

said Yuri Martina, MD, PhD, Chief Development and Medical Officer, Mundipharma.

Data from the ReSPECT programme have been submitted to the FDA and EMA for regulatory review. Rezafungin prophylaxis in adults undergoing allo-HSCT represents the investigational use evaluated in ReSPECT. This prophylaxis indication is not currently approved, and approved indications for rezafungin vary by jurisdiction.

In the United States, the FDA has granted Priority Review, with a PDUFA (Prescription Drug User Fee Act) target action date in Q1 2027.

ReSPECT is a Phase III, multicentre, randomised, double-blind study comparing once-weekly intravenous rezafungin with a daily standard antimicrobial regimen for prevention of invasive fungal disease following allo-HSCT through Week 13. Adults were randomised 2:1 to rezafungin or standard antimicrobial prophylaxis.

Rezafungin was administered as a 400 mg intravenous loading dose on Day 1 followed by 200 mg once weekly. The standard antimicrobial regimen consisted of a daily oral azole, fluconazole or posaconazole, together with trimethoprim/sulfamethoxazole following engraftment.

The primary endpoint was FFS survival at Day 90 following HSCT, a composite incorporating survival, absence of proven or probable IFD, and no use of non-study systemic antifungal therapy for more than 10 cumulative days.

(rezafungin) is the differentiated echinocandin with a unique PK/PD profile indicated for the treatment of invasive candidiasis in adults.

has approved indications for the treatment of Candida infections in both the United States and European Union;

these differ from the investigational prophylaxis setting evaluated in ReSPECT.

In the United States, REZZAYO is an echinocandin antifungal indicated in adult and paediatric patients 12 years of age or older who have limited or no alternative options for the treatment of candidemia and invasive candidiasis. Approval of this indication is based on limited clinical safety and efficacy data for REZZAYO.³ In the European Union, REZZAYO is indicated for the treatment of invasive candidiasis in adults. The EU Summary of Product Characteristics states that consideration should be given to official guidance on the appropriate use of antifungal agents.⁴ The use of rezafungin for prophylaxis of invasive fungal disease in adults undergoing allogeneic haematopoietic stem cell transplantation, as evaluated in the Phase III ReSPECT study, is investigational and is not currently an approved indication in either the United States or European Union.

Mundipharma is a global healthcare company with a presence in Africa, Asia Pacific, Canada, Europe, Latin America and the Middle East. In line with its mission, United for Patients, Mundipharma is dedicated to bringing innovative treatments to patients in the areas of pain management, infectious disease, ophthalmology, oncology, respiratory and central nervous system. For more information visit: www.mundipharma.com.

1. Maertens J. et al, Rezafungin (Once Weekly) versus Standard Antimicrobial Regimen for Antifungal Prophylaxis in Allogeneic Hematopoietic Stem Cell Transplantation: ReSPECT, a Multicentre, Randomized, Double-Blind, Phase III, Oral presentation at IDWeek 2026, 22 October 2026.
2. Quattrone M. et al, Managing Invasive Fungal Infections During Allogeneic Hematopoietic Transplantation: A 2025 Update. Mediterr J Hematol Infect Dis. 2025 Sep 1;17(1):e2025064. doi: 10.4084/MJHID.2025.064. PMID: 40937308; PMCID: PMC12422250.
3. HIGHLIGHTS OF PRESCRIBING INFORMATION REZZAYO https://www.accessdata.fda.gov/drugsatfda_docs/label/2026/217417s007lbl.pdf (last accessed October 2026)
4. Rezzayo: EPAR – Product information https://www.ema.europa.eu/en/documents/product-information/rezzayo-epar-product-information_en.pdf (last accessed October 2026)

Contacts

Liana Del Medico

VP Communications & Corporate Affairs Mundipharma