Median Time to Response (months)
 
CR
 6.6
 11.5
 6.0
 4.2
 
 
PR
 4.0
 6.2
 5.8
 —
Median Duration of Response (months)
CR
 NR
 8.3
 NR
 >7.7c (CALGB)

>15.2c (MDA)
 
PR
 NR
 15.2
 NR
 —
% Estimated to be in Response After 24 Months
 
CR
 76
 16
 85
 —
PR
 50
 21
 —
 —
Median Time to Recovery (days)
 
ANC (1500/mm3)
 70
 106
 —
 —
Platelets (100,000/mm3)
 22
 36
 —
 —
NR = Not reached by Kaplan-Meier method; ANC = Absolute neutrophil count.

aeva luable patients

bPatients either refractory to, or intolerant of, IFN

cKaplan-Meier estimate
The results show that frontline patients treated with NIPENT achieved a significantly higher rate of response than those treated with IFN. The time to recovery of neutrophil and platelet counts was shorter with NIPENT treatment and the estimated duration of response was longer. The response rate in IFN-refractory patients treated with NIPENT was similar to that in NIPENT-treated frontline patients. At a median follow-up duration of 46 months, there was no statistically significant difference in survival between hairy cell leukemia patients initially treated with NIPENT and those initially treated with IFN. However, no definite conclusions regarding survival can be made from these results because they are complicated by the fact that the majority of IFN patients crossed over to NIPENT treatment.

In the Phase 3 SWOG study, 25 patients with hairy cell leukemia died during treatment or follow-up: 18 patients had last received NIPENT (3 of whom had crossed over from IFN), and 7 patients had last received IFN (1 of whom crossed over from NIPENT). Eleven of the 25 deaths occurred within 60 days of the last dose of treatment. Of these, hairy cell leukemia was cited by the investigators as a contributory cause for 1 death in the NIPENT group and 3 deaths in the IFN group. Additionally, infection contributed to the deaths of 3 patients in the NIPENT group and 2 patients in the IFN group. Approximately 4% of hairy cell leukemia patients, in each arm, died more than 60 days after the last dose of either treatment and there was no outstanding cause of death among these patients.

INDICATIONS AND USAGE
NIPENT is indicated as single-agent treatment for both untreated and alpha-interferon-refractory hairy cell leukemia patients with active disease as defined by clinically significant anemia, neutropenia, thrombocytopenia, or disease-related symptoms.

CONTRAINDICATIONS
NIPENT is contraindicated in patients who have demonstrated hypersensitivity to NIPENT.

WARNINGS
See Boxed Warning.

Patients with hairy cell leukemia may experience myelosuppression primarily during the first few courses of treatment. Patients with infections prior to NIPENT treatment have in some cases developed worsening of their