What's next in infectious diseases — October 25, 2026

This edition covers four milestones dated between January and March 2027: three FDA decisions (inhaled liposomal amikacin for newly diagnosed MAC lung disease, once-weekly oral lenacapavir for PrEP, and rezafungin as antifungal prophylaxis in allogeneic transplant) and CROI 2027. Dates come from official sponsor or organizer announcements; the CROI dates are preliminary, and the FDA may act early, extend the review or decline.

1. Inhaled liposomal amikacin for newly diagnosed MAC lung disease

[Pending regulatory decision] [USA] [Confirmed date: January 28, 2027]
What it is: supplemental application (priority review, announced by Insmed on September 21, 2026) for full approval of amikacin liposome inhalation suspension (ALIS) as part of a combination regimen for Mycobacterium avium complex lung disease; it rests on the phase 3b ENCORE trial (NCT04677569; 425 treatment-naive patients randomized, 213 to ALIS and 212 to placebo; 82.4% with a first infection), randomized 1:1 and double-blind: ALIS or placebo (inhaled empty liposomes), both with azithromycin 250 mg and ethambutol 15 mg/kg for 12 months, plus 3 months off treatment. Primary endpoint: change in Respiratory Symptom Score (RSS) at month 13, met; per Insmed's release, improvement was 17.77 vs 14.66 points (difference 3.11; p = 0.0299). Durable culture conversion at month 15: 76.2% vs 47.6% (p < 0.0001; presented at IDWeek 2026).
What problem it solves: ALIS is currently approved (2018 accelerated approval) only for refractory disease after at least 6 months of therapy without sputum conversion; new disease is treated with the oral three-drug regimen of a macrolide, ethambutol and a rifamycin, with unsatisfactory conversion and recurrence rates.
Critical take: the background regimen did not include a rifamycin, so the comparator is not the guideline-recommended three-drug regimen; for the primary (symptom) endpoint the release gives a 3.11-point difference without a confidence interval, and the trial is sponsor-run (Insmed); cost limits its use in our setting.
https://www.prnewswire.com/news-releases/fda-grants-priority-review-to-insmeds-snda-for-arikayce-amikacin-liposome-inhalation-suspension-for-treatment-of-mac-lung-disease-with-pdufa-target-action-date-set-for-january-28-2027-302884017.html
https://investor.insmed.com/2026-03-23-Insmed-Announces-Positive-Topline-Results-from-Phase-3b-ENCORE-Study-of-ARIKAYCE-R-Amikacin-Liposome-Inhalation-Suspension-in-Patients-with-MAC-Lung-Disease?asPDF=1
https://www.ajmc.com/view/inhaled-amikacin-raises-culture-conversion-in-new-mac-lung-disease
https://clinicaltrials.gov/study/NCT04677569

2. Once-weekly oral lenacapavir for HIV pre-exposure prophylaxis

[Pending regulatory decision] [USA] [Confirmed date: February 2, 2027]
What it is: supplemental application for a once-weekly 300 mg lenacapavir tablet as PrEP; Gilead supports it with the lenacapavir profile shown in PURPOSE 1 (NCT04994509, adolescent and young cisgender women) and PURPOSE 2 (NCT04925752, cisgender men and gender-diverse people), both using the twice-yearly injectable formulation. The weekly oral form is not approved anywhere.
What problem it solves: according to Gilead, it could be the first long-acting PrEP pill; current options are the daily tablet (tenofovir plus emtricitabine), whose efficacy depends on adherence many cannot sustain, and injectables (cabotegravir every two months, lenacapavir every six months), which require clinic visits.
Critical take: the announcement cites PURPOSE 1 and PURPOSE 2, both conducted with the injectable formulation, and does not describe the weekly oral schedule data in detail; this limits independent comparison between formulations and does not allow us to anticipate what the FDA will base its decision on; with irregular dosing, an incident infection could select capsid-inhibitor resistance; access in the Dominican Republic will depend on agreements not yet announced.
https://www.gilead.com/news/news-details/2026/u-s--fda-accepts-gileads-application-for-investigational-once-weekly-oral-yeztugo-potentially-the-first-long-acting-pill-for-hiv-prevention
https://clinicaltrials.gov/study/NCT04994509
https://clinicaltrials.gov/study/NCT04925752

3. Once-weekly rezafungin as antifungal prophylaxis in allogeneic hematopoietic stem cell transplant

[Pending regulatory decision] [USA] [Estimated date: first quarter of 2027, per CorMedix]
What it is: supplemental application (priority review, announced by CorMedix on October 19, 2026) to extend rezafungin, a once-weekly intravenous echinocandin, to prophylaxis of invasive fungal disease in adults undergoing allogeneic transplant; in the phase 3 ReSPECT trial (NCT04368559), randomized 2:1 and double-blind at more than 50 centers in 7 countries, with 402 patients assigned to rezafungin and 200 to the standard antimicrobial regimen (a daily oral azole, fluconazole or posaconazole, plus trimethoprim-sulfamethoxazole after engraftment), fungal-free survival at day 90 was 60.7% vs 59.0% (estimated difference 1.6 points; 95% CI −6.2 to 9.3), a result Mundipharma reports as non-inferiority.
What problem it solves: prophylaxis currently relies on azoles (posaconazole, voriconazole, fluconazole) plus Pneumocystis prophylaxis, with relevant calcineurin-inhibitor interactions, hepatotoxicity and unreliable oral absorption in patients with mucositis; rezafungin is currently approved only for candidemia and invasive candidiasis in adults and pediatric patients 12 years of age or older who have limited or no alternative options.
Critical take: the announcements do not state the non-inferiority margin or how many patients were included in the analysis, so the non-inferiority conclusion is the sponsor's; sponsor-run trial (Mundipharma, CorMedix's partner); weekly IV administration and cost limit its interest to transplant centers.
https://www.globenewswire.com/news-release/2026/10/19/3383327/0/en/cormedix-announces-fda-acceptance-for-priority-review-of-supplemental-nda-for-rezzayo-rezafungin-for-prophylaxis-of-invasive-fungal-diseases.html
https://www.businesswire.com/news/home/20260427620065/en
https://www.mundipharma.com/mundipharma-announces-positive-topline-results-from
https://www.biospace.com/press-releases/mundipharma-announces-further-phase-iii-respect-results-presented-as-a-late-breaking-oral-presentation-at-idweek-2026
https://www.accessdata.fda.gov/drugsatfda_docs/label/2026/217417s007lbl.pdf
https://clinicaltrials.gov/study/NCT04368559

4. CROI 2027

[Conference] [USA (San Diego)] [Estimated date: March 21, 2027, per the preliminary dates published by CROI]
What it is: the Conference on Retroviruses and Opportunistic Infections will be held, per the organizers' preliminary dates (subject to change), March 21–24, 2027, in San Diego, organized by IAS-USA in partnership with the CROI Foundation; it is where trials in HIV, viral hepatitis and opportunistic infections, including new long-acting treatment and prevention regimens, are usually presented first.
What problem it solves: it concentrates in a few days the data that will change HIV practice in the following months; today that information arrives scattered across press releases ahead of publication.
Critical take: the late-breaking abstract deadline is January 19, 2027, and the program has not been published, so we cannot anticipate specific results; what is presented there are abstracts without full peer review.
https://www.croiconference.org/save-the-date-croi-2027/
https://www.croiconference.org/about/croi-2027-preliminary-important-dates-and-deadlines/

*What's next in infectious diseases — October 25, 2026*
Four dated milestones:
• Jan 28, 2027 — FDA: inhaled liposomal amikacin for newly diagnosed MAC lung disease (ENCORE)
• Feb 2, 2027 — FDA: once-weekly oral lenacapavir for HIV PrEP
• Q1 2027 (estimated, per CorMedix) — FDA: once-weekly rezafungin as antifungal prophylaxis in allogeneic transplant (ReSPECT)
• Mar 21–24, 2027 (preliminary dates) — CROI 2027, San Diego
With a critical take on each: comparators, data limitations and sponsorship.
Full text and audio: https://boletinesmedicos.com/en/infectious-diseases/2026-10-25-viene.html
MedBulletins · boletinesmedicos.com

What's next in infectious diseases: three FDA decisions and a key conference between January and March 2027.

• Inhaled liposomal amikacin for newly diagnosed MAC lung disease (January 28)
• Once-weekly oral lenacapavir for HIV PrEP (February 2)
• Once-weekly rezafungin as antifungal prophylaxis in allogeneic transplant (first quarter, estimated per CorMedix)
• CROI 2027 in San Diego (March 21–24, preliminary dates)

For each: the clinical problem it addresses, what we do today and what limits the evidence (non-standard comparators, weekly oral data not detailed in the announcement, non-inferiority without a published margin).

Full text and audio: https://boletinesmedicos.com/en/infectious-diseases/2026-10-25-viene.html

#InfectiousDiseases #HIV #PrEP #Mycobacteria #BoletinesMedicos

What's next in ID: FDA decisions expected on ALIS for new MAC (Jan 28), weekly oral lenacapavir PrEP (Feb 2) and rezafungin prophylaxis in HSCT (Q1 2027, CorMedix estimate); CROI Mar 21–24 (preliminary). Critical take on each.
https://boletinesmedicos.com/en/infectious-diseases/2026-10-25-viene.html