Ventricular arrhythmias and sudden death events following acalabrutinib initiation.

Acalabrutinib, a next-generation Bruton's tyrosine kinase inhibitor (BTKi), associates with dramatic efficacy against B-cell malignancies. Recently, unexplained ventricular arrhythmias (VAs) with next-generation BTKi-therapy have been reported. Yet, whether acalabrutinib associates with VAs in long-term follow-up is unknown. Leveraging a large-cohort of 290 consecutive B-cell malignancy patients treated with acalabrutinib from 2014 to 2020, we assessed the incidence of VAs. The primary-endpoint was incident VA development (ventricular fibrillation, ventricular tachycardia, and symptomatic premature ventricular contractions). Probability-scores were assessed to determine likelihood of acalabrutinib-association. Incident rates as function of time-on-therapy were calculated. Weighted average observed incidence rates were compared with expected population rates using relative-risks. Absolute excess risk (AER) for acalabrutinib-associated VAs was estimated. Over 1063 person-years of follow-up, there were 8 cases of incident-VAs, including 6 in those without coronary disease (CAD) or heart failure (HF) and 1 sudden-death; median time-to-event 14.9 months. Among those without prior ibrutinib-use, CAD, or HF, the weighted average incidence was 394 per 100 000 person years compared with a reported incidence of 48.1 among similar-aged non-BTKi-treated subjects (relative risk, 8.2; P < .001; AER, 346). Outside of age, no cardiac or electrocardiographic variables associated with VA development. Collectively, these data suggest VAs may be a class-effect of BTKi therapies.

Hypertension and incident cardiovascular events after next-generation BTKi therapy initiation.

BACKGROUND: Post-market analyses revealed unanticipated links between first-generation Bruton's tyrosine kinase inhibitor (BTKi) therapy, ibrutinib, and profound early hypertension. Yet, whether this is seen with novel selective second (next)-generation BTKi therapy, acalabrutinib, is unknown. METHODS: Leveraging a large cohort of consecutive B cell cancer patients treated with acalabrutinib from 2014 to 2020, we assessed the incidence and ramifications of new or worsened hypertension [systolic blood pressure (SBP) ≥ 130 mmHg] after acalabrutinib initiation. Secondary endpoints were major cardiovascular events (MACE: arrhythmias, myocardial infarction, stroke, heart failure, cardiac death) and disease progression. Observed incident hypertension rates were compared to Framingham heart-predicted and ibrutinib-related rates. Multivariable regression and survival analysis were used to define factors associated with new/worsened hypertension and MACE, and the relationship between early SBP increase and MACE risk. Further, the effect of standard antihypertensive classes on the prevention of acalabrutinib-related hypertension was assessed. RESULTS: Overall, from 280 acalabrutinib-treated patients, 48.9% developed new/worsened hypertension over a median of 41 months. The cumulative incidence of new hypertension by 1 year was 53.9%, including 1.7% with high-grade (≥ 3) hypertension. Applying the JNC 8 cutoff BP of ≥ 140/90 mmHg, the observed new hypertension rate was 20.5% at 1 year, > eightfold higher than the Framingham-predicted rate of 2.4% (RR 8.5, P < 0.001), yet 34.1% lower than ibrutinib (12.9 observed-to-expected ratio, P < 0.001). In multivariable regression, prior arrhythmias and Black ancestry were associated with new hypertension (HR 1.63, HR 4.35, P < 0.05). The degree of SBP rise within 1 year of treatment initiation predicted MACE risk (42% HR increase for each + 5 mmHg SBP rise, P < 0.001). No single antihypertensive class prevented worsened acalabrutinib-related hypertension. CONCLUSIONS: Collectively, these data suggest that hypertension may be a class effect of BTKi therapies and precedes major cardiotoxic events.