Treatment Options for Elderly/Unfit Patients with Chronic Lymphocytic Leukemia in the Era of Targeted Drugs: A Comprehensive Review

Chronic lymphocytic leukemia (CLL) incidence increases with age reaching 37.9/100,000 in patients over 85 years. Although there is no standardized geriatric tool specifically validated for CLL, a correct framing of the fitness status is of critical importance to individualize treatment strategies. Based on the evidence available to date, frontline chemoimmunotherapy has an increasingly narrowing application, being eligible for candidacy only in elderly fit patients without or with minimal geriatric syndromes. On the other hand, treatment with BCR inhibitors, monotherapy, or in combination with anti-CD20 antibodies (e.g., obinutuzumab), must be preferred both for frontline and relapsed CLL not only in unfit patients, but also in fit patients with unmutated IGHV or harboring del(17p) and/or TP53 mutations/deletions. Second-generation inhibitors (e.g., acalabrutinib, zanubrutinib, pirtobrutinib) are novel compounds that, due to their better safety profile and different specificity, will help physicians overcome some of the safety issues and treatment resistances. In the era of targeted therapies, treatment decisions in elderly and/or unfit patients with CLL must be a balance between efficacy and safety, carefully evaluating comorbidities and geriatric syndromes to ensure the best approach to improve both quality of life and life expectancy.