Previously, I’ve noted some rather concerning confusion among anti-trans activists on the subject of implanted puberty-blocking medications used in trans adolescents. Brie Jontry, a spokesperson for anti-trans hub 4thWaveNow, characterized the Vantas brand of once-yearly histrelin acetate implant as a “late-stage cancer drug” that was “never studied in young people”, and falsely claimed it was “contraindicated” for use in children. In reality, Vantas is merely “not indicated” for pediatric populations, and contains the same medication as the once-yearly Supprelin LA implant which is indicated for use in children with precocious puberty. Neither Vantas nor Supprelin LA are specifically FDA-approved for the indication of treating pediatric gender dysphoria, so the particular brand really makes no difference.
Moreover, describing this as a “late-stage cancer drug” is meant to suggest that it comes with the toxic effects of chemotherapy, when it actually treats prostate cancer by blocking the production of testosterone and other androgens which fuel the cancer’s growth. It is not a toxic chemotherapy drug; it simply shuts down the body’s own production of sex hormones, which is exactly what is intended when delaying puberty either in the context of precocious puberty in cis children, or the undesired puberty in trans children prior to hormonal transition to their desired sex. Calling it a “late-stage cancer drug”, in this context, is like calling prednisone prescribed for a sinus infection a “cancer drug”. When a medication is used for a broad variety of purposes, disingenuous outrage-mongers often won’t hesitate to jump on such an opportunity.
As it turns out, the most relevant difference between Supprelin LA and Vantas is not in the effect of these medicines, but in their pricing: Supprelin LA comes with a price tag of $37,300 for a year of treatment, with Vantas costing only $4,400. The use of Vantas in place of Supprelin LA for trans kids is quite the opposite of some big-pharma profiteering conspiracy – it is a cost-saving measure, and one that is all the more important for trans children and their families given that many insurance policies still do not cover puberty-blocking medications for gender dysphoria (Dowshen, Christensen, & Gruschow, 2019).
A recent study by Olson-Kennedy et al. (2020) provides evidence confirming that the Vantas and Supprelin LA once-yearly histrelin acetate implants are equivalent in their action when used in trans adolescents. Although both implants contain 50mg of histrelin and are intended to be used for a period of one year before being removed and possibly replaced with a new implant, Supprelin LA releases 65 micrograms of histrelin daily, while Vantas releases 50 micrograms daily. The authors studied 66 trans youth who received a histrelin implant at Tanner stage 2 or 3 of their undesired natal puberty, with 46 receiving Supprelin LA and 20 receiving Vantas.
At a followup time ranging from 2 to 12 months after insertion of the implant, transmasculine youth on Supprelin LA had their estradiol levels reduced to a median of 2 pg/mL, and those using Vantas had median estradiol levels of 3 pg/mL, a difference which was not significant. Similarly, transfeminine youth on Supprelin LA had median total testosterone levels of 9 ng/dL at followup, and those on Vantas had median levels of 7 ng/dL, which was also not a significant difference. Additionally, there were no significant differences at followup between the Supprelin LA and Vantas groups in levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). As the authors note, “all participants had achieved adequate suppression into the prepubertal range” of LH and FSH at followup time.
These results confirm that the comparatively inexpensive Vantas implant can function as an equally effective substitute for the Supprelin LA implant for the purpose of blocking natal puberty in trans adolescents. Given that these implants have been observed in some cases to continue working effectively for two years or more, this could be an opportunity for even further savings. Puberty blockers such as histrelin implants can play an important role in medical transition for trans adolescents, a treatment associated with clearly positive health outcomes, and clinicians specializing in the treatment of trans youth generally have a good idea of what they’re doing. And anti-trans activists, as usual, don’t have any idea what they’re talking about. ■
