Safety, pharmacokinetics, and pharmacodynamics of SHR7280, an oral gonadotropin-releasing hormone receptor antagonist, in healthy men: a randomized, double-blind, placebo-controlled phase 1 study

BACKGROUND

Gonadotropin-releasing hormone (GnRH) antagonists are a promising therapeutic approach for treating hormone-dependent prostate cancer. Currently, the mainstream GnRH antagonists are polypeptide agents administered through subcutaneous injection. In this study, we evaluated the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of SHR7280, an oral small molecule GnRH antagonist, in healthy men.

METHODS

This phase 1 trial was a randomized, double-blind, placebo-controlled, and dose-ascending study. Eligible healthy men were randomized in a 4:1 ratio to receive either oral SHR7280 tablets or placebo twice daily (BID) for 14 consecutive days. The SHR7280 dose was initiated at 100 mg BID and then sequentially increased to 200, 350, 500, 600, 800, and 1000 mg BID. Safety, PK, and PD parameters were assessed.

RESULTS

A total of 70 subjects were enrolled and received the assigned drug, including 56 with SHR7280 and 14 with placebo. SHR7280 was well-tolerated. The incidence of adverse events (AEs, 76.8% vs 85.7%) and treatment-related AEs (75.0% vs 85.7%), as well as the severity of AEs (moderate AEs, 1.8% vs 7.1%) were similar between the SHR7280 group and placebo group. SHR7280 was rapidly absorbed in a dose-dependent manner, with a median T_max of each dose group ranging from 0.8 to 1.0 h on day 14 and a mean t_1/2 ranging from 2.8 to 3.4 h. The PD results demonstrated that SHR7280 exhibited a rapid and dose-proportional suppression of hormones, including LH, FSH, and testosterone, with maximum suppression achieved at doses of 800 and 1000 mg BID.

CONCLUSIONS

SHR7280 showed an acceptable safety profile, as well as favorable PK and PD profiles within a dose range of 100 to 1000 mg BID. This study proposes a rationale for further investigation of SHR7280 as a potential androgen deprivation therapy.

TRIAL REGISTRATION

Clinical trials.gov NCT04554043; registered September 18, 2020.

The Efficacy and Safety of Relugolix Compared with Degarelix in Advanced Prostate Cancer Patients: A Network Meta-analysis of Randomized Trials

CONTEXT

Degarelix is associated with high rates of injection site reaction. The US Food and Drug Administration approved relugolix, an oral gonadotropin-releasing hormone (GnRH) antagonist, for the treatment of advanced prostate cancer patients.

OBJECTIVE

This systematic review and network meta-analysis aimed to compare the efficacy and safety of relugolix versus degarelix.

EVIDENCE ACQUISITION

A systematic search was performed using major web databases for studies published before January 30, 2021, according to the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) extension statement for a network meta-analysis. Studies that compared the efficacy (12-mo castration rate with testosterone ≤50 ng/dl) and safety (adverse events [AEs]) of relugolix or degarelix and of the control group (GnRH agonists) were included. We used the Bayesian approach in the network meta-analysis.

EVIDENCE SYNTHESIS

Four studies (n = 2059) met our eligibility criteria. The main efficacy analysis was conducted for two different treatments (relugolix and all doses of degarelix vs GnRH agonists); relugolix (risk ratio [RR] 1.09, 95% credible interval [CrI]: 0.95-1.23) and degarelix (RR 0.98, 95% CrI: 0.91-1.06) were not associated with different 12-mo castration rates. In the subgroup analysis, degarelix 480 mg was significantly associated with a lower castration rate (RR 0.46, 95% CrI: 0.07-0.92). In all efficacy ranking analyses, relugolix achieved the best rank. The safety analyses showed that relugolix (RR 0.99, 95% CrI: 0.6-1.6 and RR 0.72, 95% CrI: 0.4-1.3, respectively) and degarelix (RR 1.1, 95% CrI: 0.75-1.35 and RR 1.05, 95% CrI: 0.42-2.6, respectively) were not associated with either all AE or serious AE rates. In the ranking analyses, degarelix achieved the worst rank of all AEs and the best rank of serious AEs. Relugolix (RR 0.44, 95% CrI: 0.16-1.2) and degarelix (RR 0.74, 95% CrI: 0.37-1.52) were not associated with different cardiovascular event (CVE) rates; both were associated with lower CVE rates than GnRH agonists in the ranking analyses.

CONCLUSIONS

We found that the efficacy and safety of relugolix are comparable with those of degarelix, albeit with no injection site reaction. Such data should be interpreted with caution until large-scale direct comparison studies with a longer follow-up are available.

PATIENT SUMMARY

We found that relugolix, an oral gonadotropin-releasing hormone (GnRH) antagonist, has comparable efficacy and safety with degarelix, a parenteral GnRH antagonist, for the treatment of advanced prostate cancer patients.

Fixed versus flexible antagonist protocol in women with predicted high ovarian response except PCOS: a randomized controlled trial

Background

No previous study directly compares the fixed day-5 initiation versus the flexible initiation of GnRH antagonist administration in IVF/ICSI for those patients who are predicted as high ovarian responders without PCOS. To evaluate whether the number of oocytes retrieved is different by using the two GnRH antagonist protocols in Chinese women with predicted high ovarian response except PCOS.

Methods

A randomized controlled trial of 201 infertile women with predicted high ovarian response except PCOS undergoing in vitro fertilization. Ovary stimulation was performed using recombinant FSH and GnRH antagonists. GnRH antagonist ganirelix (0.25 mg/d) was started either on day 5 of stimulation (fixed group) or when LH was > 10 IU/L, and/or a follicle with mean diameter > 12 mm was present, and/or serum E₂ was > 600 pg/ml. Patient monitoring was initiated on day 3 of stimulation in flexible group.

Result(s)

No significant difference was observed between the fixed and flexible groups regarding the number of oocytes retrieved (16.72 ± 7.25 vs. 17.47 ± 5.88, P = 0.421), the Gonadotropin treatment duration (9.53 ± 1.07 vs. 9.67 ± 1.03, P = 0.346) and total Gonadotropin dose (1427.75 ± 210.6 vs. 1455.94 ± 243.44, P = 0.381). GnRH antagonist treatment duration in fixed protocol was statistically longer than the flexible protocol (6.57 ± 1.17 vs 6.04 ± 1.03, P = 0.001). There was no premature LH surge in either protocol.

Conclusion(s)

Fixed GnRH antagonist administration on day 5 of stimulation appear to achieve a comparable oocyte retrieved compared with flexible antagonist administration.

Trial registration

NCT02635607 posted on December 16, 2015 in clinicaltrials.gov.

HORMONAL THERAPY IN WOMEN OF REPRODUCTIVE AGE WITH ENDOMETRIOSIS: AN UPDATE

Medical therapy of endometriosis is under continuous reevaluation. Hereby we updated the drugs currently available or under investigation for the hormonal treatment of endometriosis.