Clomiphene citrate and human chorionic gonadotropin are both effective in restoring testosterone in hypogonadism: a short-course randomized study

The Habous et al. 2018 trial in BJU International is the head-to-head randomized comparison of the two best-evidenced HPG-axis-preserving testosterone-restoration strategies — clomiphene citrate (a selective estrogen receptor modulator that blocks hypothalamic estrogen-receptor negative feedback and lifts LH/FSH production) and human chorionic gonadotropin (an LH-receptor agonist that drives Leydig-cell testosterone production directly) — plus the combination of both, in men with hypogonadism who wished to preserve fertility. The trial is the cleanest comparative-effectiveness reading available for the structural decision between the two main pharmacological pathways through which late-onset hypogonadism can be treated without exogenous testosterone.

The design was a three-arm parallel-group randomized trial in 282 fertility-preserving hypogonadal men recruited from urology and andrology clinics. Participants were randomized to one of three treatment arms: clomiphene citrate (CC) 50 mg orally daily (n=95); hCG 5,000 IU intramuscularly twice weekly (n=94); or the combination of clomiphene 50 mg daily plus hCG 5,000 IU twice weekly (n=94). The primary endpoint was change in serum total testosterone after a short-course treatment period. Secondary endpoints included gonadotropin levels (LH, FSH), estradiol, sperm parameters where available, and tolerability.

The headline result is the equivalence. All three treatment arms produced testosterone restoration of similar magnitude — the testosterone elevation on single-agent clomiphene was statistically indistinguishable from the elevation on single-agent hCG, which was statistically indistinguishable from the elevation on the combination. The combination arm did not produce additive effects; the implication is that under the doses tested, the two agents are not synergistic for the testosterone endpoint and the choice between them is structural (route, frequency, cost, side-effect profile) rather than efficacy-driven. The directional finding — that all three pathways for HPG-axis-preserving testosterone restoration produce equivalent testosterone elevation — collapses what had been a contested practitioner-level decision into a logistics-and-tolerability decision.

Single-agent clomiphene emerges as the structurally simplest and cheapest of the three options. Oral once-daily dosing replaces twice-weekly intramuscular injection. The cost differential is substantial — clomiphene is a generic decades-old medication; hCG is a biologic with higher per-dose pricing and storage requirements. For the man whose primary constraint is fertility preservation and whose testosterone is in the borderline-to-mildly-low range, the Habous result supports clomiphene as the first-line pharmacological intervention, with hCG reserved for the man who does not tolerate clomiphene's side-effect profile (mood symptoms, occasional visual disturbance, gastrointestinal symptoms are the most-cited reasons for discontinuation) or who needs the higher-magnitude testicular stimulation hCG can deliver at higher doses (Coviello et al. 2005 for the dose-response architecture).

For andropause-and-peptides, the Habous trial is the operational reference for the decision tree at the fertility-preserving end of the spectrum. The dossier frames clomiphene, hCG, and the combination as three structurally different pathways into the same outcome (testosterone restoration with HPG-axis preservation), and Habous is the empirical basis for treating them as efficacy-equivalent at the doses tested. The hCG peptide page cross-links to this trial for the head-to-head context; the conservatism-of-starting-with-clomiphene framing in the dossier rests on the Habous result combined with the cost-and-route advantages.