Drugs of interest to pathologists
Drugs related to surgical pathology
Bexarotene
Copyright: (c) 2002-2019, PathologyOutlines.com, Inc.
PubMed Search: Bexarotene [title] review
Drugs related to surgical pathology
Bexarotene
Author: Him G. Kwee, M.D.
Topic Completed: 1 December 2011
Minor changes: 22 August 2019
Copyright: (c) 2002-2019, PathologyOutlines.com, Inc.
PubMed Search: Bexarotene [title] review
Table of Contents
Definition / general | Trade name | Clinical information | Pathophysiology | Side effectsCite this page: Kwee HG. Bexarotene. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/drugstargretin.html. Accessed August 6th, 2020.
Definition / general
- A retinoid that selectively activates retinoid X receptors
Trade name
- Targretin® (oral and topical)
Clinical information
Approved by U.S. Food and Drug Administration for:
- Cutaneous T cell lymphoma (CTCL) that is refractory to at least one prior systemic therapy
- The oral capsules are used for generalized CTCL and the topical gel is used for localized plaques with CTCL
- It has been used "off label" for lung carcinoma, breast carcinoma and Kaposi sarcoma (Wikipedia: Bexarotene [Accessed 14 December 2018])
- A clinical trial using bexarotene gel for alopecia areata is in progress
- Approximate costs: $2,600 for 30 days oral therapy for adult taking 150 mg, $1,800 for 60 gm topical gel (links now invalid)
Pathophysiology
- Bexarotene selectively binds and activates retinoid X receptors RXR alpha, RXR beta and RXR gamma
- RXRs can form heterodimers with various receptor partners such as retinoic acid receptors (RARs), vitamin D receptor, thyroid receptor and peroxisome proliferator activitor receptors (PPARs)
- Once activated, these receptors function as transcripton factors that regulate the expression of genes that control cellular differentiation and proliferation
- However, the exact mechanism of action of bexarotene in the treatment of CTCL is unknown (Drugs.com: Targretin [Accessed 14 December 2018])
Side effects
- Lipids: bexarotene can cause elevations in serum triglyceride and LDL cholesterol and a decrease in HDL cholesterol; the triglyceride elevation can cause acute pancreatitis
- Liver: elevations in AST, ALT, bilirubin, LDH, cholestasis and liver failure
- Skin: photosensitivity, acne, rash (macular, papular, vesicular, bullous or pustular), alopecia and exfoliative dermatitis (PDR Staff: Physicians' Desk Reference, 66th edition, 2012)
- Thyroid: decreases in TSH and T4 with hypothyroidism
- Blood counts: leukopenia, neutropenia, anemia, eosinophilia, increase or decrease in platelet count
- May cause false increase in serum CA 125 assay values
