Economic burden associated with adverse events of special interest in patients with relapsed Philadelphia chromosome-negative B-cell acute lymphoblastic leukemia in the United States.

BACKGROUND: Infections, cytopenia, and gastrointestinal (GI) toxicity are adverse events of special interest (AESI) affecting most relapsed Philadelphia chromosome-negative (Ph-) B-cell acute lymphocytic leukemia (ALL) patients. This study quantified real-world rates and economic burden of these events among relapsed Ph- B-cell ALL patients in the United States.

METHODS: Adults with relapsed Ph- B-cell ALL during 1 April 2009-31 October 2016 were selected from MarketScan® healthcare claims databases. Outcomes included proportions of patients with AESIs and AESI-related costs during 100 days after relapsed hospitalization.

RESULTS: Of 400 relapsed Ph- B-cell ALL patients, 92.5% experienced ≥1 AESI during the median 100-day follow-up, of which 64.6% had infections, 94.6% cytopenia, and 46.2% GI toxicities. Mean (SD; median) AESI-related total cost per patient during follow-up was $197,213 ($308,551; $105,731), with a mean of 2 AESI-related hospitalizations comprising 32.2 inpatient days. Mean (SD; median) healthcare costs were highest for infections ($164,461 [$347,083; $64,528]), followed by cytopenia ($125,210 [$165,141; $67,475]) and GI events ($11,652 [$40,231; $1349]).

CONCLUSION: The economic burden of AESIs is substantial, with infections the most expensive, followed by cytopenia and GI toxicity. New therapies that can improve outcomes in relapsed Ph- B-cell ALL while offering a favorable safety profile are needed.