A Randomised Dose De-Escalation Safety Study of Oral Fludarabine, ±Oral Cyclophosphamide and Intravenous Rituximab (OFOCIR) As First-Line Therapy of Fit Patients with Chronic Lymphocytic Leukaemia (CLL) Aged ≥65 Years – End of Recruitment Analysis of Response and Toxicity of the Australasian Leukaemia and Lymphoma Group (ALLG) and CLL Australian Research Consortium (CLLARC) CLL5 Study
Authors: Mulligan Stephen P , Gill Devinder S , Turner Paul , Renwick William E. P. , Harrup Rosemary , Latimer Maya , Mackinlay Naomi , Berkahn Leanne , Simpson David , Campbell Philip , Tiley Campbell , Cull Gavin , Collins Marnie , Cortissos Paul , Sulda Melanie , Best Giles , Kuss Bryone J 
Published: October 2019

Abstract
Abstract 436

Background:
Combination immunochemotherapy with fludarabine (F), cyclophosphamide (C) and rituximab (R) gave superior progression free and overall survival compared to FC in the CLL8 Study. The median age in CLL8 was 61 years compared to a median age for overall CLL patients of 72 years. There is ongoing debate regarding the tolerability and safety of FCR in elderly patients, and what are the most appropriate criteria for selection of therapy.

Methods:
Previously untreated patients with progressive CLL aged ≥65 were randomised to one of three treatment regimens FR5, FCR3 and FCR5 as follows: (i) F 24mg/m2 po D1-5 + R (375 mg/m2 C1, 500mg/m2 C2-6) iv D1 (FR5), (ii) F 24mg/m2 po and C 150mg/m2 po D1-3 + R iv D1 (FCR3) or (iii) F 24mg/m2 po + C 150mg/m2po D1-5 + R iv D1 (FCR5), all given at 4 weekly intervals for an intended 6 cycles. The dosage of FCR5 is equivalent to standard 3 day IV FCR in the CLL8 Study. Patients were administered their therapy arm with no dose reduction but fludarabine dose was reduced if the eGFR was 50–69ml/min. Therapy was delayed up to 2 weeks if there was grade 3 or 4 toxicity, and if unresolved after 2 weeks, patients were taken off study. If toxicity resolved to grade 2 or less, therapy proceeded.

Results:
Recruitment of all 120 randomised patients was completed in July 2012. An analysis was performed with a cut-off date of 5 May, 2012 at which time there were 117 of 120 recruited from 29 centres in Australia and New Zealand. Median age was 71.7 (range 65–83) years. Binet stage at registration was progressive A – 20 (17.1%), B – 55 (47.0%) and C – 42 (35.9%). Response data are shown in table 1 for the total patient cohort - no analysis has been performed to date by treatment arm. Analysis of grade 3 and 4 toxicity events by Cumulative Illness Rating Scale (CIRS) score and age are shown in Tables 2 and 3 with data available at the cut-off date.

Conclusions:
Oral F(C)R therapy appears generally safe and well tolerated in CLL patients aged ≥65 years requiring first-line treatment according to data available at end of recruitment. Using stringent stopping criteria with delay of 2 weeks for recovery of grade 3 or 4 toxicity but no dose reduction, ∼40% of patients stop early due to toxicity, intercurrent illness or patient choice. Based on the 66 patients with completed Final Pathological Staging 2 months after end of therapy, response rates appear high with an overall response rate (ORR) of 92.3%. For this relatively fit elderly patient cohort, neither a CIRS score of 0 to 6, nor age predicted for grade 3 and 4 toxicity.

Disclosures:
Mulligan: Roche: Consultancy, Research Funding, Speakers Bureau; Genzyme: Consultancy, Research Funding, Speakers Bureau.