Johan Maertens, MD, PhD, Professor of Hematology at University Hospitals Leuven (UZ Leuven) in Belgium and Principal Investigator of the OASIS study, discusses positive phase 3 trial results evaluating oral olorofim in patients with invasive aspergillosis.
Understanding Invasive Aspergillosis
Invasive aspergillosis is a potentially life-threatening fungal infection that typically affects the lungs. Studies show it occurs in about 13% of hospitalized immunocompromised patients. The infection is difficult to diagnose, which can delay appropriate treatment and increase the risk of mortality. Treatment options are also limited, especially in those who cannot tolerate or respond to available mold-active azole antifungals.
Symptoms of invasive aspergillosis vary from patient to patient and depend on which organs or systems the fungus invades. Telltale signs include fever, chills, shortness of breath, severe sinus pain or pressure, and, in some cases, seizures.
Phase 3 OASIS Study Demonstrates Non-Inferiority of Olorofim
Positive topline results from the global phase 3 OASIS study (NCT05101187) were announced on June 18, 2026, with additional findings presented at a late-breaking oral session at IDWeek 2026 on October 22, 2026.
OASIS was a randomized, global study evaluating oral olorofim versus intravenous AmBisome (liposomal amphotericin B), a polyene antifungal medication, followed by standard of care in adults with invasive aspergillosis whose infections were refractory to or unsuitable for azole therapy.
The study enrolled 225 participants randomized 2:1 to receive olorofim or a liposomal amphotericin B-based standard of care. The primary endpoint was all-cause mortality at day 42. Olorofim achieved non-inferiority, with all-cause mortality rates of 23.8% compared to 24.3% for liposomal amphotericin B followed by standard of care. The difference between treatment groups was -0.5%. Other outcomes, including clinical response rates, were also comparable between the two treatment groups.
Safety Findings Favor Olorofim
No new safety findings were observed with olorofim. However, the investigational antifungal demonstrated a more favorable tolerability profile than liposomal amphotericin B-based standard of care.
Specifically, drug-related treatment-emergent adverse events occurred in 35.8% of olorofim-treated patients compared to 63.9% of patients receiving the liposomal amphotericin B-based standard of care. According to Dr. Maertens, this difference was primarily due to a higher rate of renal events in the liposomal amphotericin B group.
The October 2026 IDWeek presentation also reported drug-induced liver injury (DILI) findings. Events considered at least possibly related to study treatment occurred in 4.6% of patients receiving olorofim and 4.2% of those receiving liposomal amphotericin B-based standard of care.
Dr. Maertens shared that nephrotoxicity occurred in approximately 22% of patients receiving liposomal amphotericin B compared to fewer than 2% receiving olorofim. Participants receiving olorofim also had hospital stays approximately 11 days shorter than those receiving liposomal amphotericin B, which Dr. Maertens attributed to its oral formulation and improved tolerability.
Olorofim’s Potential to Change Invasive Aspergillosis Treatment
Dr. Maertens discussed several potential advantages that olorofim might offer if approved:
- Oral administration could allow patients to continue treatment at home versus remaining hospitalized for intravenous infusions.
- The drug’s improved tolerability could reduce treatment-related complications, including kidney toxicity.
- Olorofim could provide another treatment option for patients who are unable to take azole antifungals because of resistance, toxicity, or drug-drug interactions.
Patients undergoing cancer treatment or stem cell transplantation would benefit most, because many antifungal medications interact with cancer drugs and other medications.
Olorofim is an investigational antifungal and hasn’t been approved by regulatory authorities. If it does receive approval, it would become the first antifungal with a novel mechanism of action for invasive aspergillosis in more than 20 years.
In Their Own Words
“We desperately need new drugs that we can give to these patients without compromising their leukemia treatment or their transplant prospects.” – Johan Maertens, MD, PhD, Principal Investigator of the OASIS study.
For more information, visit: https://www.globenewswire.com/news-release/2026/10/21/3385084/0/en/f2g-and-shionogi-report-data-from-global-phase-3-oasis-study-evaluating-investigational-oral-olorofim-versus-ambisome-followed-by-standard-of-care-in-invasive-aspergillosis-in-late.html
To learn more about aspergillosis and other rare lung diseases, visit: https://checkrare.com/diseases/lung-diseases/