PharmacoKINEtics of TAMoxifen and Its Metabolites in Breast Cancer Patients: the Influence of a Dose Increase in Phenotypic Poor Metabolizers of CYP2D6 (KINETAM)

NCT01192308 | Completed Phase 1

• 1 other identifier: KINETAM
• Study Type: interventional
• Target: 42
• Locations: 1 country
• Sites: 1

Brief Summary

All women on tamoxifen receive the standard dose of 20mg QD, irrespective of the use of potential CYP2D6 inhibitors, and are not tested for CYP2D6 polymorphisms prior to start of tamoxifen treatment.However CYP2D6 polymorphisms and/or the use of CYP2D6 inhibitors as co-medication may influence the treatment outcome of tamoxifen. The investigators propose a prospective study in women taking tamoxifen at a dose of 20mg QD. In each woman, information will be collected on endoxifen levels, CYP2D6 status, adherence and use of co-medication. In women who are phenotypically poor metabolizers of tamoxifen, a dose increase to 40mg QD will be applied and the effect of this intervention on tamoxifen pharmacokinetics will be evaluated after 4 weeks.

Conditions

Breast Cancer

Keywords

Breast cancer; Tamoxifen; Pharmacokinetics; Pharmacogenetics; CYP2D6

Outcome Measures

Primary Outcomes (1)

• Tamoxifen and metabolites plasmaconcentration

  Trough samples

  week 0 and 4

Secondary Outcomes (1)

• Adverse events

  week 0 and 4

Study Arms (1)

40mg QD dose intervention

EXPERIMENTAL

40mg QD dose intervention during 4 weeks in patients with CYP2D6 variant allele or using CYP2D6 inhibitor.

Drug: Tamoxifen 40mg QD

Interventions

Tamoxifen 40mg QD DRUG

Tamoxifen 40mg QD during 4 weeks

Also known as: Nolvadex

40mg QD dose intervention

Eligibility Criteria

• Age: 18 Years+
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Subject is at least 18 years at screening.
• Subject is able and willing to sign the Informed Consent Form prior to screening evaluations.
• Subject is a female patient with (a history of) breast cancer and has been treated with tamoxifen 20mg QD for at least 4 weeks and is expected to be treated for at least another 4 weeks

You may not qualify if:

• Inability to understand the nature and extent of the trial and the procedures required.
• Participation in a drug trial within 60 days prior to the first dose.

Sponsors & Collaborators

• Radboud University Medical Center: lead

Study Sites (1)

Radboud University Nijmegen Medical Centre

Nijmegen, Netherlands

Location

Related Publications (1)

• Welzen ME, Dezentje VO, van Schaik RH, Colbers AP, Guchelaar HJ, van Erp NP, den Hartigh J, Burger DM, van Laarhoven HW. The Effect of Tamoxifen Dose Increment in Patients With Impaired CYP2D6 Activity. Ther Drug Monit. 2015 Aug;37(4):501-7. doi: 10.1097/FTD.0000000000000195.

  PMID: 26192892 RESULT

MeSH Terms

Conditions

Breast Neoplasms

Interventions

Tamoxifen

Condition Hierarchy (Ancestors)

Neoplasms by Site; Neoplasms; Breast Diseases; Skin Diseases; Skin and Connective Tissue Diseases

Intervention Hierarchy (Ancestors)

Stilbenes; Benzylidene Compounds; Benzene Derivatives; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals

Study Officials

• David M Burger, PharmD, PhD

  Radboud University Medical Center

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: August 30, 2010
• First Posted: September 1, 2010
• Study Start: July 1, 2010
• Primary Completion: May 1, 2011
• Study Completion: May 1, 2012
• Last Updated: December 1, 2020

Record last verified: 2020-11

Locations

NL (1)