Table 3. Reported outcomes for commonly used treatment options for hairy cell leukemia (primary or relapsed).

Regimen	No.	Objective response rate, %	Complete remission rate, %	Comment
Single-agent cladribine (0.1 mg/kg per day for  7 days, continuous infusion) [78, 101]	349	98	91	96 % of patients were alive after 4 years; relapse  rate was 16 % for those who achieved  complete remission and 54 % for those who  achieved a partial response; outcomes were  better in patients who achieved complete  remission
Single-agent cladribine (0.1 mg/kg per day for  7 days, continuous infusion) [104]	85	100	79	87 % of patients were alive after 12 years; 36 %  experienced relapse after 10 years of follow-up
Single-agent cladribine (0.12 mg/kg per day,  2-hour intravenous bolus for 5 days vs. every  week for 6 weeks) [107]	68	95	76	Similar response and survival outcomes with  both schedules of cladribine
	64	91	72
Single-agent pentostatin (4 mg/m2  intravenously every 2 weeks for 6 months)  [94•]	154	79	76	This randomized trial confirmed the superiority  of pentostatin over IFN-α; after 9 years of  follow-up, 83 % of patients were alive[99]
Single-agent pentostatin (4 mg/m2 intravenous  bolus once every 2 weeks until maximum  response or failure) [131]	238	96	79	Estimated 5-year and 10-year overall survival  rates of 89 %
Single-agent cladribine (5.6 mg/m2  intravenously over 2 hours daily for 5 days  followed by 375 mg/m2 intravenous  rituximab weekly for 8 weeks) [91••]	31	100	100	After a median follow-up period of 2 years,  median progression-free and overall survival  durations had not been reached