Assess the economic impact of the fixed-duration regimen of venetoclax and obinutuzumab (VenO) versus the continuous treatment with ibrutinib (Ibr) in patients with untreated Chronic Lymphocytic Leukemia (1L CLL) in the Brazilian private market. Cost-minimization (CMM) and budget impact (BIM) models were developed in the perspective of the Brazilian private market. Due to the lack of direct comparisons between VenO and Ibr in 1L CLL and limitations of indirect analysis, similar efficacy results were applied in clinical practice for both comparators. Therefore, only direct-costs related to drug-use and dosage according respective labels were considered. Purchased prices were obtained from price-reference list, published by the Brazilian Regulatory Agency (ANVISA-June/2020), considering list prices with 18% of taxes. The CMM analyzed, in term of incremental costs, the total treatment costs in 2 years. A sub-analysis was developed considering expected time-use of Ibr in 1L (7 years). The BIM considered the adult eligible population in private market with a reference scenario (100% Ibr) and an alternative scenario (100% VenO). A sub-analysis with 17p deletion/TP53 and IGVH unmutated population was also included. According to CMM, over 2 years VenO generated an incremental cost-savings of US$77,021 per patient. Although in the first year VenO offers incremental cost of US$9,911, in the second year it saves US$87,032 per patient. Over 7 years, VenO offers an incremental cost-savings of US$512,284 per patient, and a saving-ratio of ten patients treated with Ibr (1L CLL) is the same cost of about 62 patients treated wih VenO. According to BIM, VenO offers the potential to reduce budget impact in US$911,451,818 in 5 years. The fixed-duration treatment of VenO provides cost-minimization compared to continuous treatment with Ibr monotherapy. In all assessed scenarios, VenO generates significant resource-savings to the Brazilian Private Healthcare System without compromising efficacy in 1L CLL patients.