Pralsetinib / Solid Tumor Malignancies / CYP3A4, CYP2C8, and CYP2C9 substrates, and hormonal contraceptive · Phase 4 Trial

Pralsetinib DDI Study in Patients With Advanced or Metastatic Solid Tumors

ClinicalTrials.gov · August 10, 2026

Preliminary Why this matters to you Expert discussion

Early or partial results. Treat as a signal, not a conclusion.

AI Summary

This is a clinical trial registry record for a Phase 4 open-label study of pralsetinib drug-drug interactions with CYP450 substrates and hormonal contraceptives in patients with RET-positive solid tumors. No results are posted in this registry record; the study is currently recruiting and designed to measure plasma concentration profiles of probe substrates co-administered with pralsetinib.

What was studied

Phase 4, Interventional, Single Group, Open label, Other purpose. NSCLC (Non-small Cell Lung Cancer), Thyroid Cancer, Solid Tumor Malignancies, Advanced Malignancies; age from 18 Years. Intervention: Pralsetinib with CYP450 Probe Substrates and Hormonal Contr…. n = 12. 2 sites: Spain.

Key findings

Safety

No comparator or control arm is described; this is a single-arm pharmacokinetic study.

Who this may help

Once results are available, this study will inform dosing and safety considerations for pralsetinib when used concurrently with CYP3A4, CYP2C8, or CYP2C9 substrate drugs and hormonal contraceptives. At present, no clinical impact can be drawn from a registry record without posted results.

Plain-language summary

This is a Phase 4 interventional study registration with no results posted; it describes planned pharmacokinetic endpoints in a small estimated cohort and cannot support clinical efficacy or safety conclusions.

Study design

As stated by the source record.

MethodsPrimary outcome measures: Area Under the Plasma Concentration-Time Curve from zero to infinity (AUC0-inf) (assessed at Up to 48 hours post-dose or as appropriate for each probe substrate); Area under the plasma concentration-time curve from time zero to time of last measurable concentration (AUClast) (assessed at Up to 48 hours after each probe drug administration); Maximum Peak Plasma Concentration (Cmax) (assessed at Up to 48 hours after each probe drug administration)

DesignPhase 4, Interventional, Single Group, Open label, Other purpose

PopulationNSCLC (Non-small Cell Lung Cancer), Thyroid Cancer, Solid Tumor Malignancies, Advanced Malignancies; age from 18 Years

Sample size12

InterventionPralsetinib with CYP450 Probe Substrates and Hormonal Contr…

Setting2 sites: Spain

Reported figures

Quoted from the source exactly as published.

Estimated enrollment12

Primary outcome measure 1Area Under the Plasma Concentration-Time Curve from zero to infinity (AUC0-inf), up to 48 hours post-dose or as appropriate for each probe substrate

Primary outcome measure 2Area under the plasma concentration-time curve from time zero to time of last measurable concentration (AUClast), up to 48 hours after each probe drug administration

Primary outcome measure 3Maximum Peak Plasma Concentration (Cmax), up to 48 hours after each probe drug administration

Clinical bottom line

Caveats

This is a registry record; no results are reported. Study status is 'RECRUITING' and conduct details (randomization, blinding, follow-up duration, analysis plan) are not provided in the source.
Open-label design without blinding; assessment of PK parameters may be subject to observer bias.
Very small estimated sample size (12 participants) limits generalizability of findings once available.
No comparator or control arm is described; this is a single-arm pharmacokinetic study.

Evidence assessment

Graded across the dimensions that decide whether you should act, each from what the source actually supports. There is no single score, and where a dimension was not assessed it says so.

Study design

moderate

Open-label Phase 4 interventional DDI study with planned PK endpoints.

Directness

moderate

Measures pharmacokinetic interactions relevant to clinical drug safety.

Consistency

insufficient

Registry record only; no results reported for comparison.

Risk of bias

limited

Open-label design without blinding; DDI studies typically have inherent observer bias risk.

Sample adequacy

limited

Estimated 12 participants; small sample for a Phase 4 study.

What is missing. This record has no key findings. That is a gap in the analysis, not a judgement about the study.

Source abstract

Registry record from ClinicalTrials.gov (NCT07704658). This is a study registration, not published results. Lead sponsor: Rigel Pharmaceuticals. Recruitment status: RECRUITING. Phase: PHASE4. Study type: INTERVENTIONAL. Enrollment: 12 participants (ESTIMATED). Conditions: NSCLC (Non-small Cell Lung Cancer), Thyroid Cancer, Solid Tumor Malignancies, Advanced Malignancies. Interventions: DRUG: Pralsetinib; DRUG: CYP3A4, CYP2C8, and CYP2C9 substrates, and hormonal contraceptive. Primary outcome measures: Area Under the Plasma Concentration-Time Curve from zero to infinity (AUC0-inf) , Up to 48 hours post-dose or as appropriate for each probe substrate; Area under the plasma concentration-time curve from time zero to time of last measurable concentration (AUClast) , Up to 48 hours after each probe drug administration; Maximum Peak Plasma Concentration (Cmax) , Up to 48 hours after each probe drug administration. Brief summary: An open-label drug-drug interaction study to evaluate the effects of pralsetinib (Gavreto) on the pharmacokinetics of a CYP450 probe substrate cocktail and, in female participants, a hormonal probe substrate, in participants with rearranged during transfection (RET) fusion- or mutation-positive solid tumors

Follow from this

Taken from the source record, never inferred. Follow any of these and new work involving them reaches your briefing.

PralsetinibNCT07704658Solid Tumor MalignanciesRigel PharmaceuticalsCYP3A4, CYP2C8, and CYP2C9 substrates, and hormonal contraceptiveNSCLC (non Small Cell Lung Cancer)Thyroid Cancer