Effect of Oral Cimetidine in the Protoporphyrias

Model scores of the 29,894 trials active now.

Model score 9% for any early termination, 4% for termination due to slow enrollment. Past trials like this one (phase, sponsor type and disease area, started 2008–2016) ended terminated 26% of the time (136 trials).

Finished trial that started in 2015 or later: the model never saw it during training.

Cumulative chance of ending terminated (red) or completed (green) by each year from its start; it actually ended on 2025-04-24. The rest of the way to 100% is still running.

From the competing-risks survival model (termination vs completion, still-running trials censored), fit to trials that started 2008–2014 and recalibrated to termination rates over 2022–2024, since termination has become more common. Checked on past years, it still ran a little low when the rise continued.

• Design: crossover (lowers risk) · Design
• Accepts healthy volunteers: No (raises risk) · Who can join
• Wording of the registration (title, summary, criteria) (lowers risk) · Wording Phrases that raised it: transplantto determinemarrowlifeenrollment
  Phrases that lowered it: and safetyparticipantefficacy andparticipantsmoderate
• Sponsor's past termination rate: no earlier finished trials (lowers risk) · Sponsor's track record
• Responsible party: sponsor investigator (raises risk) · Design
• Phase: 2 (raises risk) · Design
• Blinding: quadruple (lowers risk) · Design
• Sponsor type: academic or other (raises risk) · Sponsor's track record
• Drug's FAERS reports with a death: 13.2% (lowers risk) · Drug's FDA history
• Disease area, cancer: No (lowers risk) · Disease area
• Has a data monitoring committee: Yes (raises risk) · Design
• Collaborators: 2 (lowers risk) · Design
• Trials the sponsor started in the prior 2 years: 0 (raises risk) · Sponsor's track record
• Number of arms: 2 (raises risk) · Design
• Primary purpose: treatment (raises risk) · Design
• Maximum age: not given (raises risk) · Who can join
• Disease area, neurology: No (lowers risk) · Disease area
• Drug's FAERS reports before start: 9151 (raises risk) · Drug's FDA history
• Minimum age: 15 (raises risk) · Who can join
• Sponsor's past trials: 0 (lowers risk) · Sponsor's track record

Every input that moved this score, largest first: SHAP contributions in log-odds, red raising risk and green lowering it. They describe the model, not causes of termination. Phrases are traced from the text features back to this registration's words, approximately.

• Study of Bitopertin to Evaluate the Safety, Tolerability, Efficacy, and PPIX Concentrations in Participants With EPP NCT05308472 · started 2022 · scored riskier than 15% of active trials completed
• Study to Evaluate Efficacy, Safety, and Tolerability of MT-7117 in Subjects With Erythropoietic Protoporphyria NCT03520036 · started 2018 · scored riskier than 17% of active trials completed
• Controlled Trial of Panhematin in Treatment of Acute Attacks of Porphyria NCT02180412 · started 2014 · scored riskier than 70% of active trials completed
• Sorbent Therapy of the Cutaneous Porphyrias NCT01422915 · started 2011 · scored riskier than 9% of active trials completed
• GATEWAY: A Phase 2a Study of PORT-77 in Adults With Erythropoietic Protoporphyria NCT06971900 · started 2025 · scored riskier than 11% of active trials completed

Closest by meaning of the registration text (PubMedBERT embeddings), among finished trials. How they ended is context, not an input to this trial's score.