Pirtobrutinib Dosage and Administration: Recommended Dosage, Dose Modifications

For Patients with Severe Renal Impairment

(1). If the current dose is 200 mg once daily, reduce the pirtobrutinib dose to 100 mg once daily.

(2). If the current dose is other than 200 mg once daily, reduce the dose by 50 mg.

(3). If the current dose is 50 mg once daily, discontinue pirtobrutinib.

(4). For patients with mild to moderate renal impairment (eGFR 30-89 mL/min), dose modification of pirtobrutinib is not recommended.

Dose Modifications for Concomitant Use with Strong CYP3A Inhibitors

(1). Avoid Concomitant Use

Concomitant use of pirtobrutinib with strong CYP3A inhibitors should be avoided.

(2). Dose Modification if Concomitant Use is Unavoidable

a. If concomitant use is necessary, reduce the pirtobrutinib dose by 50 mg.

b. If the current dose is 50 mg once daily, interrupt pirtobrutinib treatment for the duration of the strong CYP3A inhibitor use.

(3). Resuming Treatment after Discontinuation

After discontinuing the strong CYP3A inhibitor for 5 half-lives, resume pirtobrutinib at the dose used before concomitant use.

Dose Modifications for Concomitant Use with CYP3A Inducers

Concomitant use of pirtobrutinib with strong or moderate CYP3A inducers is prohibited. If concomitant use with a moderate CYP3A inducer is unavoidable:

(1). When the current pirtobrutinib dose is 200 mg once daily, increase the dose to 300 mg once daily.

(2). If the current dose is 50 mg or 100 mg once daily, increase the dose by 50 mg (i.e., adjust to 100 mg or 150 mg once daily, respectively).