Pf729 long‐term Proteasome Inhibition (Ltpi) in Patients (Pts) With Newly Diagnosed Multiple Myeloma (Ndmm): Us Mm‐6, a Real‐world (Rw) Study Transitioning From Bortezomib (Btz) to Ixazomib (Ixa)

Abstract

was 80 mg (10 mg daily for children < = 15years). Patients with baseline uric acid level >8 mg/dl, presence of hepatic or renal dysfunction and history of receiving rasburicase were excluded. The primary objective was to compare both the drugs in terms of decrease in serum uric acid levels analysed by area under curve (AUC) for a 7-day treatment period. Results: A total of 120 patients (60 patients in each group) were recruited. Both groups were comparable in terms of gender, age, diagnosis and baseline uric acid levels. Mean AUC of serum uric acid day1-8 was 457.68 ± 27.55 mg-h/dL versus 532.32 ± 34.39 mg-h/dL, in favour of febuxostat [P = 0.09]. The difference between the two study drugs was statistically significant for febuxostat on day+3 [P < 0.05] (Figure 1).10% (n = 6) patients on allopurinol developed TLS compared to 3.33% (n = 2) patients on febuxostat. The Odds ratio for tumor lysis syndrome in patients receiving febuxostat relative to those receiving allopurinol was 0.33. Drug related adverse events were 38.33% (n = 23) in allopurinol group, in contrast to 11.66% (n = 7) in the febuxostat group. Most common adverse event in allopurinol arm was gastrointestinal, whereas in febuxostat arm, it was asymptomatic transaminitis. Cutaneous reactions (6.6%;n = 4) were noticed only in allopurinol group. Summary/Conclusion: Irrespective of type of leukemia, lactate dehydrogenase levels, leukocyte counts and baseline uric acid levels, febuxostat in comparison to allopurinol, performed non-inferior with respect to its uric acid lowering efficacy. It had relatively lesser risk of tumor lysis syndrome with a trend towards significance and a better safety profile.