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Pharmacokinetic Boosting of Olaparib to Improve Exposure, Tolerance and Cost-effectiveness

Pharmacokinetic Boosting of Olaparib to Improve Exposure, Tolerance and Cost-effectiveness

Status
Recruiting
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05078671
Acronym
PROACTIVE
Enrollment
160
Registered
2021-10-14
Start date
2021-12-15
Completion date
2025-12-31
Last updated
2024-06-12

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Cancer

Keywords

olaparib, pharmacokinetic enhancement

Brief summary

Olaparib is a poly-adenosine diphosphate ribose polymerase (PARP) inhibitor, originally used for the maintenance treatment of women with platinum-sensitive relapsed breast cancer gene (BRCA)-mutated high grade serious epithelial ovarian, fallopian tube, or peritoneal cancer, who are in response to platinum-based chemotherapy. Over the last two years, several therapeutic indications have been added to the drug label, such as first-line platinum-sensitive BRCA-mutated high grade serious epithelial ovarian, fallopian tube, or peritoneal cancer, germline BRCA1/2-mutated, human epidermal growth factor 2 (HER2-)negative, locally advanced or metastatic breast cancer and BRCA1/2-mutated metastatic castration-resistant prostate cancer, who have progressed following prior therapy. Since olaparib is very expensive, this increase of treatment population will have a significant impact on health care expenditures. To keep healthcare affordable and accessible for all patients, innovative strategies are warranted to reduce the dose of expensive drugs, without reduction of efficacy. For olaparib, pharmacokinetic (PK) boosting can be applied. PK boosting is the lay term for administering a non-therapeutic active strong inhibitor of a metabolic enzyme, for example the cytochrome p450 enzyme 3A (CYP3A), together with a therapeutic drug that is metabolized by the same enzyme. Boosting thus increases the concentration of the therapeutic drug and allows lower doses to be administered to patients. Hence, coadministration of a reduced dose of olaparib with cobicistat, a non-therapeutic, strong inhibitor of the CYP3A can lead to equivalent exposure to olaparib. Furthermore, inhibition of CYP3A could lead to less PK variability since metabolic capacity is a prominent cause for (intra- and inter-individual) variability in systemic exposure. Predictable olaparib exposure will reduce the number of patients who are unintentionally under- or overtreated. Lastly, tumor tissue itself may express CYP3A as a detoxification or resistance mechanism. Theoretically, PK boosting may also overcome CYP3A-mediated drug resistance. The purpose of this study is to establish the efficacy, safety and feasibility of co-administering olaparib with the PK booster cobicistat with the aim to implement boosting approach for olaparib in routine practice. The study is subdivided in two parts. In part A of the study the equivalent exposure of boosted low dose olaparib is determined compared to the normal dose. In part B of the study, non-inferiority of the boosted olaparib regimen will be confirmed.

Interventions

DRUGOlaparib

olaparib treatment

DRUGCobicistat

Pharmacokinetic booster

Sponsors

Radboud University Medical Center
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Intervention model description

Part A: cross-over normal olaparib versus boosted olaparib. Part B: normal olaparib versus boosted olaparib in two patient groups.

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Subjects who are able and willing to provide written informed consent prior to screening; * Age of 18 years or older; * Able to measure the outcome of the study in this subject. Part A: * Subjects who start or are on treatment with olaparib tablets 300mg twice daily, according to the drug label and physician's discretion; * Eastern Cooperative Oncology Group (ECOG) performance status of 0-1. Part B: * Subjects who start on treatment with olaparib tablets 300mg twice daily, according to the drug label and physician's discretion; * Expected to be on olaparib treatment for ≥ 3 months; * ECOG performance status of 0-3.

Exclusion criteria

* Concurrent use of other anti-cancer therapies; * Concurrent use of potent inducers or inhibitors of the cytochrome p450 enzyme 3A3 (CYP3A4) as assessed with the Dutch drug database G-Standaard of the Royal Dutch Pharmacists Association(KNMP); * Known contra-indications for treatment with cobicistat in line with the summary of product characteristics; * Subjects with renal insufficiency defined as estimated glomerular filtration rate \< 50 ml/min.

Design outcomes

Primary

MeasureTime frameDescription
Part B: Progression-free survival (PFS)12 monthsPFS is defined as time from randomization until the date of either objective radiological disease progression, or biochemical progression combined with clinical progression or death.
Part B: Dose reductions12 monthsNumber of patients who require a dose reduction due to toxicity.
Part A: Olaparib AUC0-12h2 weeksThe Area-Under-the-Curve (AUC) 0-12h of olaparib.

Secondary

MeasureTime frameDescription
Part B: Health status12 monthsHealth status as assessed with the EuroQol 5 dimensions with 5 levels questionnaire (EQ-5D-5L).
Part B: Patient satisfaction12 monthsPatient satisfaction as assessed with the Cancer Therapy Satisfaction Questionnaire (CTSQ).
Part B: Adverse events12 monthsNumber of patients with treatment-related adverse events as assessed by CTCAE v5.0.
Part B: Productivity costsFrom date of randomization until the date of end-of-treatment, assessed up to 12 monthsProductivity costs as assessed by the iMTA Productivity Costs Questionnaire (iPCQ).
Part B: Medical consumptionFrom date of randomization until the date of end-of-treatment, assessed up to 12 monthsMedical consumption as assessed by the iMTA Medical Consumption Questionnaire (iMCQ).
Part B: ctDNA12 weeksCell-free tumor nucleic acids (ctDNA) in plasma as pharmacodynamic biomarker.
Part A: Inter- and intrapatient variability of AUC0-12h2 weeksInter- and intrapatient variability of AUC0-12h in olaparib as calculated with non-compartmental analysis.
Part A: Adverse events2 weeksNumber of patients with treatment-related adverse events as assessed by CTCAE v5.0.

Other

MeasureTime frameDescription
Part A: Patient preference2 weeksTreatment preference on a 7-point Likert scale.
Part B: Intratumoral olaparibAt 8 weeks after start treatment and at the moment of progressionIntratumoral olaparib concentration in tumor biopsy samples.

Countries

Netherlands

Contacts

Primary ContactJoanneke K Overbeek, PharmD
joanneke.overbeek@radboudumc.nl+31-24-3617744

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 6, 2026