Retatrutide yields 18.8% weight loss in type 2 diabetes; orforglipron meets cardiovascular safety goal; FDA approves tiratricol

Eli Lilly reported phase 3 results for retatrutide and orforglipron at the European Association for the Study of Diabetes (EASD) meeting in Milan, with both trials published simultaneously in The Lancet. The Food and Drug Administration (FDA) approved tiratricol as the first treatment for MCT8 deficiency, and Lilly said a phase 2b combination of eloralintide and tirzepatide produced up to 23.3% weight loss.

  • Research Sept 29, 2026
    In the phase 3 TRIUMPH-2 trial, published in The Lancet, 1,152 adults with obesity and type 2 diabetes were randomized to the triple agonist retatrutide 4 mg, 9 mg or 12 mg or placebo. With 12 mg, body weight fell 18.8% at week 80, versus 5.1% with placebo, under the abstract's treatment-regimen estimand; Eli Lilly reported 20.8% versus 4.0% under the efficacy estimand, with up to 40.0% reaching an A1C below 5.7%. Discontinuations for adverse events were 3.8% to 11.6% with retatrutide and 4.9% with placebo, Lilly said. TRIUMPH-1 appeared in the New England Journal of Medicine the same day.
  • Research Sept 30, 2026
    In the open-label ACHIEVE-4 trial of 2,749 adults with type 2 diabetes at increased cardiovascular risk, published in The Lancet, orforglipron (Foundayo) met the noninferiority criterion versus insulin glargine for four-point major adverse cardiovascular events (hazard ratio 0.84; 95% CI 0.59 to 1.20). Lilly said the all-cause death hazard ratio for orforglipron versus glargine was 0.43 (95% CI 0.25 to 0.75) in pre-planned analyses not controlled for family-wise type 1 error. It said A1C fell 1.6% with orforglipron and 1.0% with glargine at 52 weeks under the efficacy estimand, and 10.6% of orforglipron patients stopped treatment for adverse events.
  • FDA Sept 28, 2026
    The Food and Drug Administration approved Emcitate (tiratricol) tablets for oral suspension to treat peripheral thyrotoxicosis in patients with MCT8 deficiency, also known as Allan-Herndon-Dudley syndrome, the first therapy approved for the disorder's symptoms. Tiratricol enters cells without relying on the defective MCT8 transporter, the agency said. In two studies, including a randomized, placebo-controlled trial, treated patients had lower excess thyroid hormone levels and improved cardiovascular and metabolic symptoms. Common side effects were diarrhea, vomiting, rash and excessive sweating; Egetis Therapeutics received the approval.
  • Research Sept 30, 2026
    Lilly reported that EloraTZP, an investigational combination of the amylin receptor agonist eloralintide and tirzepatide, produced up to 23.3% weight loss at 48 weeks in a phase 2b trial of 367 adults with obesity or overweight and type 2 diabetes, versus 14.8% with tirzepatide 15 mg, under the efficacy estimand. A1C fell by up to 2.9%, versus 2.4% with tirzepatide. Discontinuations for adverse events ranged from 10.8% to 27.0% with the combination, versus 2.9% with tirzepatide, HCPLive reported. Lilly said it plans to start phase 3 studies of a co-formulated EloraTZP product by the end of 2026.
    Sources: Eli Lilly, HCPLive

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