Week of 13 to 19 October 2026. This edition covers research published or announced by 15 October.
Oral peptides are at the centre of two developments this week: a trial report in ulcerative colitis and the start of larger studies in obesity. Elsewhere, a full phase 3 report on rusfertide joins new laboratory work on cancer delivery and the chemistry used to build complex peptides. The findings range from controlled human trials to early discovery research, so each answers a different kind of question.
Oral icotrokinra improves ulcerative colitis response
An oral peptide that blocks the interleukin 23 receptor produced more clinical responses than placebo in a phase 2b ulcerative colitis trial. At 12 weeks, response rates were 63%, 58% and 55% across the three icotrokinra dose groups, compared with 27% on placebo. The highest dose also improved clinical remission and endoscopic measures, making this a useful test of whether a targeted peptide can work as an oral treatment in this condition.
Key details: The ANTHEM-UC trial randomised 252 adults with moderately to severely active ulcerative colitis to once daily icotrokinra or placebo. At the 400 mg trial dose, clinical remission was 30% versus 11% with placebo, and endoscopic improvement was 37% versus 14%. The New England Journal of Medicine published the report online on 14 October.
Limitations: This was a sponsor funded phase 2b study, not a confirmatory phase 3 trial. The main efficacy comparison covered 12 weeks, while adverse events were reported through week 28. The 200 mg remission comparison did not meet its prespecified statistical threshold, which stopped further formal testing of secondary endpoints in the planned sequence. Longer follow up is needed to assess lasting benefit and less common harms.
Rusfertide gains a full phase 3 trial report
The full peer reviewed VERIFY report adds detail to the evidence for rusfertide in polycythaemia vera, a blood disorder involving excess red blood cell production. Among 293 participants, 77% receiving rusfertide alongside standard care met the trial's clinical response endpoint during weeks 20 to 32, compared with 33% receiving placebo alongside standard care. The report also found fewer phlebotomies, the blood removal procedures used to control haematocrit in this condition.
Key details: Rusfertide is a hepcidin mimetic peptide given once weekly by subcutaneous injection in the trial. Response meant avoiding eligibility for phlebotomy during the specified assessment period. Mean phlebotomies over the 32 week comparison were 0.5 with rusfertide and 1.8 with placebo. The Journal of Clinical Oncology published the report on 13 October; the main results had already been disclosed in 2025, so this is a new full publication rather than a first announcement of the findings.
Limitations: The controlled results cover 32 weeks in people whose polycythaemia vera required phlebotomy despite standard care. They do not establish long term outcomes or apply automatically to every person with the condition. Injection site reactions and anaemia were among the common adverse events.
Oral VK2735 moves into phase 3 obesity studies
Viking Therapeutics has announced the start of two phase 3 studies of oral VK2735, an investigational peptide targeting GLP-1 and GIP receptors. SUNRISE-1 will study adults with obesity or qualifying overweight without type 2 diabetes, while SUNRISE-2 will study adults with overweight or obesity and type 2 diabetes. The programme will test whether the weight changes seen in earlier development hold up in larger, longer comparisons with placebo.
Key details: The 14 October announcement describes two randomised, double blind trials, each with a planned enrolment of 560 adults. Participants will receive one of three once daily doses or placebo over 68 weeks. The primary endpoint is percentage change in body weight at week 68.
Limitations: This is a trial launch announcement, not a report of phase 3 results. Enrolment numbers are targets, and no SUNRISE efficacy or safety findings are available in this announcement. Earlier phase 2 findings are separate evidence and should not be presented as outcomes from these new studies.
VYQFF peptide helps test a cancer delivery approach
A short peptide called VYQFF has been attached to brucine carrying liposomes in new head and neck cancer research. The formulation showed greater uptake in the HSC3 cancer cells tested than in HOK comparison cells, reduced cell proliferation and increased apoptosis in laboratory experiments. The researchers also reported reduced tumour growth in a mouse xenograft model.
Key details: Published on 13 October in ACS Applied Materials & Interfaces, the study examined a peptide modified delivery system rather than a peptide acting alone as an anticancer drug. It combined cell experiments with an animal model. Exact effect sizes and animal group sizes could not be confirmed from the publicly accessible abstract.
Limitations: These are preclinical findings, with no human trial. Fluorescence retention after injection into a tumour does not prove that the formulation would find tumours selectively after systemic administration, or that it binds specifically to Trop2. The limited toxicology and proposed mechanism need further testing.
A new route to complex macrocyclic peptides
A Nature Synthesis paper describes a new way to make tryptophan crosslinked macrocyclic peptides, structures that can be difficult to assemble. Using rhodium catalysis and a removable directing group, the team formed a carbon to nitrogen bond within the peptide to close the ring. The approach was applied to structures related to micitide 982 and the antibiotic tryglysin, potentially widening access to molecules for future research.
Key details: The peer reviewed version was published on 13 October, following an earlier preprint. Representative synthesis examples in the supplementary experiments reported isolated yields from 54% to 98%. Those numbers describe how much chemical product was recovered, not a biological response or treatment effect.
Limitations: This is a chemistry advance, not an efficacy study. The work does not establish activity, exposure, safety or clinical benefit for the resulting compounds. The authors also disclose a provisional patent application covering the method.