Idelalisib (Specialist drug)

PRESCRIBING: treatment should be conducted by a physician experienced in the use of anti-cancer therapies. MISSED DOSE: if missed within 6 hours of the usual time, take it as soon as possible and resume the normal schedule; if missed by more than 6 hours, skip it and resume the usual schedule. DOSE MODIFICATIONS (the reduced dose is 100 mg twice daily in every case) — ELEVATED TRANSAMINASES: withhold for Grade 3 or 4 ALT/AST elevation (greater than 5 x ULN); once values return to Grade 1 or below (ALT/AST 3 x ULN or less) resume at 100 mg twice daily, with re-escalation to 150 mg twice daily at the physician's discretion if the event does not recur; if it recurs, withhold again until Grade 1 or less and consider re-initiation at 100 mg twice daily. DIARRHOEA/COLITIS: withhold for Grade 3 or 4; once returned to Grade 1 or below resume at 100 mg twice daily, with re-escalation to 150 mg twice daily at the physician's discretion if it does not recur. PNEUMONITIS: withhold for suspected pneumonitis; once resolved and if re-treatment is appropriate, resumption at 100 mg twice daily can be considered; permanently discontinue for moderate or severe symptomatic pneumonitis or organising pneumonia. RASH: withhold for Grade 3 or 4; once returned to Grade 1 or below resume at 100 mg twice daily, with re-escalation at the physician's discretion. NEUTROPENIA: maintain dosing at ANC 1,000 to less than 1,500/mm3; maintain dosing with at least weekly ANC monitoring at ANC 500 to less than 1,000/mm3; interrupt at ANC below 500/mm3 and monitor ANC at least weekly until ANC is 500/mm3 or more, then resume at 100 mg twice daily. MONITORING AND PROPHYLAXIS: do not initiate in patients with evidence of ongoing systemic bacterial, fungal or viral infection; Pneumocystis jirovecii pneumonia prophylaxis should be given to all patients throughout treatment and for 2 to 6 months after discontinuation; monitor for CMV in patients with positive CMV serology or a history of CMV infection; monitor blood counts at least every 2 weeks for the first 6 months of treatment and at least weekly while ANC is less than 1,000/mm3; monitor for respiratory signs and symptoms. HEPATIC: no dose adjustment when initiating in mild (Child-Pugh A) or moderate (Child-Pugh B) impairment but with intensified monitoring of adverse reactions; insufficient data for dose recommendations in severe hepatic impairment — caution and intensified monitoring. ELDERLY: no specific dose adjustment at 65 years or older. PAEDIATRIC: safety and efficacy in children under 18 years have not been established; no data are available.