Low dose of ketoconazole in patients with prostate adenocarcinoma resistant to pharmacological castration

The Efficacy of Ketoconazole Containing Regimens in Castration-Resistant Prostate Cancer: A Systematic Review and Meta-Analysis

Castration resistant prostate cancer (CRPC) is a challenging subset of prostate cancer associated with an extensive metastatic profile and high mortality. Ketoconazole is a nonselective steroid 17α-hydroxylase/17,20 lyase (CYP17A1) inhibitor and is employed as a second line treatment option for CRPC with an established efficacy profile in patients. The aim of this study is to assess the efficacy of ketoconazole containing regimens for CRPC in terms of prostate specific antigen (PSA) decline rate using a systematic review and meta-analysis. In this review, an electronic search was carried out on PubMed, Cochrane CENTRAL, Scopus, and Google Scholar to find relevant literature. Random effects model was used to assess pooled PSA decline rate and 95% CIs. Publication bias was assessed using the funnel plot symmetry and one-tailed Egger's and Begg's test. In all cases, P-value <.05 was indicative of significant results. The review is registered with PROSPERO: CRD42023466536. A total of 483 articles were retrieved after database searching, out of which 23 studies (having a total of 1315 patients) were included in the review based on prespecified criteria. The PSA decline rate was reported in the 14 observational studies (having 964 patients) and 9 experimental studies (having 351 patients). Pooled results revealed that 48.6% (95% CI 43.1-54.2; P-value <.001; I2 = 73.24%) of participants achieved more than 50% decline in PSA (602/1315 participants). Sensitivity analysis using the leave-one-out method revealed no substantial change in pooled effect estimates; (Risk Ratio) RR 47.2% to RR 49.8% demonstrating the robustness of our results. There was no evidence of publication bias as assessed from the funnel plot symmetry. Ketoconazole containing regimens have shown moderate efficacy in high risk CRPC patients as demonstrated by the pooled results. Hence, a ketoconazole based chemotherapy can be added to patients' regimen if there is a persistent rise in PSA levels after androgen deprivation therapy.

Abiraterone acetate in castration-resistant prostate cancer

The palliative goal of the treatment of metastatic prostate cancer is to prolong survival and decrease cancer-related complications. Androgen ablation therapy is widely accepted as the initial treatment of choice; when the disease becomes resistant to castration-resistant prostate cancer (CRPC), docetaxel-based chemotherapy aids in prolonging overall survival and controlling disease-related symptoms. Until a few years ago, no drug had showed efficacy in docetaxel-resistant patients. Recently, cabazitaxel, a taxane family compound, has been shown to help prolong survival in patients previously treated with docetaxel, even if a high grade of myelotoxicity has been reported. Moreover, a better understanding of the biology of CRPC has demonstrated that prostate cancer proliferation is largely mediated through the androgen receptor, which could be reactivated by androgens produced by the adrenal glands. Abiraterone acetate is an orally active acetate salt of the steroidal compound abiraterone with antiandrogen activity. Abiraterone inhibits the enzymatic activity of steroid 17α-monooxygenase, a member of the cytochrome P450 family that catalyzes the 17α-hydroxylation of steroid intermediates involved in testosterone synthesis from the adrenal glands. This review focuses on abiraterone acetate, the first compound that, through the inhibition of adrenal gland production of testosterone, increases the overall survival in CRPC patients. The role of possible predictive biomarkers and future perspectives are also discussed.

Post-docetaxel therapy in castration resistant prostate cancer - the forest is growing in the desert

In Europe, prostate cancer is the most common cancer among men with 382.000 new cases and 89.000 deaths annually. Historically, androgen deprivation therapy and docetaxel based chemotherapy were the only treatments able to improve survival. Two studies have been published during last few months regarding the management of castration resistant prostate cancer (CRPC) progressed after docetaxel: for the first time second line therapies have been demonstrated to improve prognosis of these patients. The relevance of these trials is the reintroduction of chemotherapy and hormonal therapy in a disease once considered chemotherapy and castration resistant. All these data may change the traditional approach to CRPC but no evidences have came out from recently closed or ongoing clinical trials about the therapeutic algorithm. How to get oriented in this forest? We propose that patient's conditions, response and toxicities reported with previous treatments and, above all, dynamics and evolution of disease may influence the choice of subsequent therapies in docetaxel progressed CRPC.

The prognostic factors of effective ketoconazole treatment for metastatic castration-resistant prostate cancer: who can benefit from ketoconazole therapy?

We investigated the prognostic value of some variables of effective ketoconazole treatment for metastatic castration-resistant prostate cancer (mCRPC). In total, 163 patients with mCRPC were eligible, receiving ketoconazole 200-400 mg three times daily with replacement doses of prednisone. Progression-free survival (PFS) was calculated from the beginning of the ketoconazole therapy to the onset of disease progression. The prognostic value of different variables for PFS was assessed by Cox regression analysis. The median PFS was 2.6 months (0.5-8.6 months) for these patients. The serum testosterone level changed during therapy, which decreased when the prostate-specific antigen (PSA) declined; the serum testosterone level increased as the levels of PSA relapsed. The median PFS values for patients associated with different factors were the following: 1.4 and 3.5 months for a nadir PSA of ≥ 0.2 and <0.2 ng ml(-1), respectively (hazard rate (HR)=4.767, P<0.001); 3.1 and 1.6 months for a baseline testosterone of ≥ 0.1 and <0.1 ng ml(-1), respectively (HR=2.865, P=0.012); 2.8 and 1.9 months for a baseline haemoglobin of ≥ 120 and <120 g l(-1), respectively (HR=1.605, P<0.001); and 3.0 and 1.9 months for a PSA doubling time (PSADT) of ≥ 2.0 and <2.0 months, respectively (HR=1.454, P=0.017). A risk model was constructed according to the four factors that divided patients into three subgroups of low risk (0-1 factors), moderate risk (2 factors) and high risk (3-4 factors) with PFS values of 3.6, 3.0 and 1.4 months, respectively (HR=1.619, P<0.001). A nadir PSA of ≥ 0.2 ng ml(-1), a baseline testosterone of <0.1 ng ml(-1), a baseline haemoglobin of <120 g l(-1) and a PSADT of <2 months were associated with a poor PFS. This risk model could provide evidence to predict the survival benefit of ketoconazole therapy.