Bosentan REMS requirements for prescribers and pharmacies
Bosentan REMS still requires liver monitoring, certification and patient enrollment. Learn what changed for pregnancy rules and what pharmacies must check.
The bosentan REMS remains in place for Tracleer and generic bosentan to manage liver-injury risk. FDA removed the pregnancy-related REMS requirements in fall 2025, but kept certification, patient enrollment and monthly liver monitoring (FDA's March 4, 2026 page).
The duties below are FDA requirements for US prescribers and pharmacies. REMS checks and prescribing-information precautions are separate obligations. Bosentan remains contraindicated in pregnancy even though the pregnancy-related REMS requirements have ended (FDA).
What changed in the bosentan REMS program?
FDA modified the bosentan program rather than eliminating it. The fall 2025 change removed the embryo-fetal-toxicity requirements from the REMS. What remains is a hepatotoxicity program for liver injury, covering Tracleer and generic bosentan (FDA status page).
Ambrisentan and macitentan-containing products took a different path. FDA eliminated their REMS entirely in April 2025, and prescribers, pharmacies and patients no longer need to participate in those programs. Bosentan kept its REMS. And an ambrisentan or macitentan REMS notice is the wrong basis for a bosentan dispensing change (FDA).
What prescribers and patients must do
The FDA bosentan listing describes a single shared-system REMS with elements to assure safe use (ETASU). The monitoring objective is monthly liver-enzyme checks during treatment, as described in the prescribing information. Prescribers must review the prescribing information and the Prescriber Guide, then enroll for certification. They still have to complete the patient-specific steps below before the first dose.
Before the first dose, the prescriber must take these steps from the FDA program listing:
- Counsel the patient about liver injury, its symptoms and when to contact the prescriber.
- Explain the liver-testing requirement and provide the Patient Guide.
- Assess liver function and document it on the Patient Enrollment Form.
- Enroll the patient and give them a completed copy of the form.
During treatment, the prescriber must assess liver function and counsel the patient monthly. Adverse events suggestive of hepatotoxicity must be reported to the REMS (FDA program listing).
Patients have their own requirements. Before treatment, they must review the Patient Guide, receive counseling, obtain a liver test and enroll with the prescriber. Before each prescription, they must receive counseling, obtain a liver test and confirm completion with the REMS or the pharmacy. They must also report signs or symptoms of liver problems to the prescriber (FDA REMS record).
What pharmacies must check before dispensing
Certification and the dispense check are different jobs. The listing requires certification through an authorized representative, review of the Pharmacy Guide and training for relevant staff. Outpatient dispensing and inpatient discharge do not share one supply rule (FDA REMS record).
Outpatient pharmacies
Before an outpatient pharmacy dispenses, it must obtain REMS authorization. Authorization confirms that the patient is enrolled, the prescriber and pharmacy are certified, and counseling is complete. It also confirms that liver testing is complete, or that the prescriber has authorized the refill as the listing describes. Outpatient dispensing is limited to no more than a 30-day supply (FDA REMS record).
If testing or counseling is not documented, confirm the testing or provide the counseling, then submit that confirmation through the REMS website or contact center rather than treating the step as an upload of laboratory values. Prescriber authorization of a refill is a listed option. It is not a standing permission to skip testing. The conditions sit in the approved REMS Document.
Inpatient pharmacies and discharge
Inpatient pharmacies must be certified too. Before dispensing, verify that the patient is enrolled, or will be enrolled before discharge, that the prescriber is certified, and that counseling and liver testing are complete. At discharge, dispense no more than a 15-day supply. Do not apply the outpatient 30-day limit to that supply (FDA REMS record).
Pharmacy duties continue after a single dispense. The listing also covers staff training, hepatotoxicity adverse-event reporting, restrictions on transfers to non-certified dispensers, recordkeeping and audits, so use the approved materials for the procedure rather than treating this overview as the dispensing checklist (FDA REMS record).
Pregnancy precautions still apply
Removing the pregnancy-related REMS requirements doesn't make bosentan safe in pregnancy. FDA says these endothelin receptor antagonists remain contraindicated in pregnancy because animal studies indicate potential fetal harm. Prescribers should exclude pregnancy before treatment, advise effective contraception during treatment and counsel about fetal risk. Patients who can get pregnant should ensure they are not pregnant before starting treatment and use effective contraception during treatment. Those points are prescribing-information precautions, not surviving pregnancy-related REMS dispensing conditions (FDA).
For a pregnancy-testing schedule or the details of contraception, use the current prescribing information. The REMS change does not replace that label (FDA's update).
Use the approved materials for implementation
The FDA listing used here was updated on March 3, 2026. The record warns that the page is a general summary and does not replace the approved REMS Document. Before you change an enrollment or dispensing procedure, read the approved document and the applicable program guides. Use the current prescribing information for laboratory thresholds and decisions about stopping or restarting treatment.
RegAffairs AI provides a citation-backed answer on bosentan REMS requirements.