Source: FDA, National Drug Code (US) Revision Year: 2026
ZENBEXUS is indicated, in combination with daratumumab and hyaluronidase-fihj and dexamethasone, for the treatment of adult patients with multiple myeloma who have received at least 1 prior line of therapy including a proteasome inhibitor and an immunomodulatory agent.
This indication is approved under accelerated approval based on minimal residual disease (MRD)-negative complete response (CR) at any time [see Clinical Studies (14)]. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial(s).
Females of reproductive potential must have negative pregnancy testing and use effective contraception methods before initiating ZENBEXUS [see Warnings and Precautions (5.1) and Use in Specific Populations (8.3)].
The recommended dosage of ZENBEXUS is 1 mg orally once daily with or without food [see Clinical Pharmacology (12.3)] on Days 1 to 21 of a 28-day cycle, until disease progression or unacceptable toxicity, in combination with daratumumab and hyaluronidase-fihj and dexamethasone.
The recommended dosage modifications for adverse reactions are provided in Table 1.
Table 1. Recommended Dosage Modifications for Adverse Reactions:
| Adverse Reaction | Severity* | Dosage Modification† |
| Neutropenia (Absolute neutrophil count [ANC] <500 cells/mcL) [see Warnings and Precautions (5.4)] | Grade 4 | • Interrupt ZENBEXUS. • Consider initiating granulocyte colony-stimulating factor (GCSF), as appropriate. • Follow complete blood count (CBC) at least weekly. • ANC must return to ≥1,000 cells/mcL before restarting. • The dose of ZENBEXUS may be maintained if neutropenia was the only ZENBEXUS-related toxicity requiring a dose modification and GCSF treatments are continued. • If a dose reduction is clinically appropriate, decrease ZENBEXUS to 0.75 mg once daily when restarting treatment. |
| Febrile Neutropenia (ANC <1,000 cells/mcL with a single temperature of >38.3°C [101°F] or with a sustained temperature of ≥38°C [100.4°F] for more than 1 hour) | Grade 3 | |
| Thrombocytopenia (platelet count <25,000/mcL) | Grade 4 | • Withhold ZENBEXUS for the remainder of the cycle. • Platelet count must return to ≥50,000/mcL before restarting. • Decrease ZENBEXUS to 0.75 mg once daily when restarting treatment. |
| Thrombocytopenia with bleeding or any requirement for a platelet transfusion | Grade 3 | |
| Thromboembolism [see Warnings and Precautions (5.3)] | ≥ Grade 3 | • Interrupt ZENBEXUS. • Initiate anticoagulant therapy. • Restart treatment at a decreased ZENBEXUS dose to 0.75 mg once daily when acute symptoms of thrombosis/embolism have been resolved, at the discretion of the treating physician. |
| Other ZENBEXUS related adverse reactions [see Adverse Reactions (6.1)] | ≥ Grade 3 | • Interrupt ZENBEXUS. • Restart ZENBEXUS when adverse event has resolved or improved to ≤ Grade 2. • If a dose reduction is clinically appropriate, decrease ZENBEXUS to 0.75 mg once daily when restarting treatment. |
* Based on National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE), Version 5.0.
† Refer to daratumumab and hyaluronidase-fihj and dexamethasone Prescribing Information for information about dosage modifications for daratumumab and hyaluronidase-fihj and dexamethasone.
Avoid concomitant use of ZENBEXUS with strong or moderate CYP3A inhibitors.
If concomitant use with strong CYP3A inhibitors is unavoidable, reduce ZENBEXUS dose to 1 mg every other day on Days 1 to 21 of a 28-day cycle [see Drug Interactions (7.1) and Clinical Pharmacology (12.3)].
If concomitant use with moderate CYP3A inhibitors is unavoidable, reduce ZENBEXUS dose to 0.75 mg once daily on Days 1 to 21 of a 28-day cycle [see Drug Interactions (7.1) and Clinical Pharmacology (12.3)]. If dose modification is needed due to adverse events, reduce ZENBEXUS dose to 1 mg every other day on Days 1 to 21 of a 28-day cycle.
In patients with eGFR less than 30 mL/min/1.73 m² not receiving dialysis, reduce ZENBEXUS dose to 0.75 mg once daily on Days 1 to 21 of a 28-day cycle. If dose modification is needed due to adverse events, reduce ZENBEXUS dose to 1 mg every other day on Days 1 to 21 of a 28-day cycle.
In patients with eGFR greater than 30 mL/min/1.73 m² or eGFR less than 30 mL/min/1.73 m² receiving intermittent hemodialysis, no dose adjustment is recommended [see Use in Specific Populations (8.6) and Clinical Pharmacology (12.3)].
ZENBEXUS is a hazardous drug. Follow applicable special handling and disposal procedures.1
Take ZENBEXUS at approximately the same time each day with or without food [see Clinical Pharmacology (12.3)].
Swallow ZENBEXUS capsules whole with water. Do not open, break, or chew the capsules. Direct contact with the capsule contents should be avoided. In case of capsule breakage, avoid raising dust during clean-up. If contact occurs, wash thoroughly with soap and water.
If a dose is missed and it has been less than 12 hours since the missed dose, take the missed dose as soon as possible. If it has been more than 12 hours since the missed dose, skip the missed dose. Do not double the next dose.
Store at 20°C to 25°C (68°F to 77°F); excursions permitted between 15°C to 30°C (59°F to 86°F).
Store and dispense in the original bottle with desiccant. Replace the cap securely each time after opening. Do not discard the desiccant.
The capsules should not be removed until just prior to dosing.
ZENBEXUS is a hazardous drug. Follow applicable special handling and disposal procedures.1
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