However, those agents have different toxicity profiles and medical costs. Although oncological outcomes and cost-effectiveness of upfront DOC or ABI were compared,8-11 it remains unclear whether the results can be translated into clinical practice. Thus, we aimed to investigate the impact of the type of upfront therapy on efficacy and medical costs in mHSPC patients with a high tumor burden during progression-free survival 2 (PFS2). This multicenter retrospective study included 340 patients with mHSPC treated with either upfront DOC or upfront ABI between October 2015 and December 2021. The inclusion criteria were: 1) histologically proven adenocarcinoma or clinically diagnosed PC, 2) met the CHAARTED high-volume criteria or LATITUDE high-risk criteria (high tumor burden),7,12 and 3) treated with ADT plus upfront intensive therapy (DOC or ABI) as the standard of care. We compared PFS2 and medical costs between the two treatment groups. PFS2 was defined as the time from first-line therapy to progression on second-line therapy. Medical costs were estimated using the National Health Insurance drug prices in 2022 in Japan.
The upfront DOC and ABI groups included 107 and 233 patients, respectively. The metastatic castration-resistant PC progression-free survival was significantly shorter in the upfront DOC group compared with the upfront ABI group (median 37 vs. 23 months, P < 0.001, HR 0.55). However, no significant differences in PFS2 were observed between the two treatment groups (median 56 vs. 43 months, P = 0.137, HR 1.43). Monthly medical costs per patient were significantly higher in the upfront ABI group ($3453) compared with the costs in the upfront DOC group ($1239, P < 0.001). The cost differences were significantly influenced by differences in the length of androgen deprivation therapy monotherapy (DOC group, 13.4 months vs. ABI group, 0.0 months).
This is the first study to evaluate oncological outcomes, AEs, and medical costs up to PFS2 in real-world practice. As multiple similar treatments are available for mHSPC in clinical practice, it is important determining whether the treatment effect is worth the cost in the interval until PFS2. We found monthly medical costs per patient were significantly higher in the upfront ABI group compared with the costs in the upfront DOC group ($3453 vs. $1239, P < 0.001). This observation was more pronounced in patients without mCRPC progression (9.1-fold cost difference) compared with cost differences in patients with mCRPC progression (1.7-fold cost difference). It should be noted that costs in the upfront DOC group were still lower compared with costs in the upfront ABI group, even in patients with CRPC progression. Given the similar antitumor effects, upfront DOC might be the more cost-effective option for men with mHSPC who were eligible for docetaxel. The cost disadvantage of the ABI group is mainly owing to the high cost of ABI. In recent years, a generic ABI has become available, and the cost disadvantage has been overcome in areas where the generic drug is available. In our setting, ABI at a 63% discount ($10.4 for 250 mg) would be comparable to DOC. The average retail price of ABI in the U.S. is $89.7 for 250 mg, whereas the generic drug is $2.18-$43.83 for 250 mg13. ABI is expected to be highly profitable if the generic drug is approved in Japan. The medical cost of triplet therapy is a further concern. This treatment will undoubtedly be the most expensive, and the question will be whether the benefits will be worth the cost (Fig.1).
Fig. 1 Estimated cost of each treatment
Written by: Shingo Hatakeyama MD, PhD, Department of Urology, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.
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