Round 13 Open Questions

Answered this round

  • Pancreatitis absolute risk: ✓ Not statistically significant elevated in meta-analyses of 17 RCTs (RR 1.29-1.46, all NS); ~10 cases per 4328 patients (<0.3%); amylase/lipase elevated asymptomatically — not equivalent to pancreatitis; gallbladder disease IS elevated (class effect — rapid weight loss triggers gallstones)
  • Real-world outcomes in T2D: ✓ Multiple US registry studies (HIRD, academic centre, TriNetX) confirm trial-level HbA1c and weight reductions; GLP-1 RA naïve patients respond most; tirzepatide favoured over semaglutide in propensity-matched T2D real-world data; TriNetX CV/mortality signal (HR 0.54/0.33) likely confounded

Still unanswered

  1. Long-term outcomes in T2D beyond 2 years: No published data beyond 104 weeks in T2D. Is there evidence of continued HbA1c and weight maintenance, or attenuation of response? SURPASS-CVOT 5-year follow-up data expected in future publications.

  2. Older T2D patients (≥70 years) — specific evidence: SURPASS trials enrolled adults 18+, but specific outcomes in those ≥70 with frailty, sarcopenia risk, polypharmacy are not well characterised. Any SURPASS subgroup analyses for older patients?

  3. Drug interactions — levothyroxine and other medications: HealthUnlocked data suggests thyroid hormone dosing may need adjustment. Any formal pharmacokinetic interaction studies? What about warfarin, immunosuppressants, or narrow therapeutic index drugs?

  4. Stopping tirzepatide — clinical management: SURMOUNT-4 shows glycaemic rebound after stopping in obesity. What is the recommended clinical approach for T2D patients who need to stop tirzepatide (surgery, side effects, supply shortage)? Bridging strategy?

  5. Tirzepatide and insulin reduction/cessation in T2D: SURPASS-6 shows it can replace basal insulin. Can tirzepatide enable insulin dose reduction or cessation in patients on full basal-bolus regimens? Any data beyond SURPASS-5/6?