(300) Impact of Intranasal Testosterone versus Intramuscular Testosterone cypionate on Hematocrit of Hypogonadal Men: Data from an ongoing Phase IV, Open-label, Randomized Clinical Trial.

Abstract

Abstract Introduction The potential increase in hematocrit and subsequent risk of polycythemia has been regarded as one of the most worrisome adverse effects of testosterone therapy (TT). Recent evidence has shown that the modality of delivery and half-life of each formulation may affect the incidence of these side effects. Therefore, we hypothesized that longer-acting intramuscular testosterone would increase hematocrit to a higher degree than the shorter-acting nasal formulations that can more closely mimic normal physiology. Objective To compare the effects of Intranasal Testosterone (NT) and Intramuscular Testosterone (TC) on hematocrit and serum testosterone levels in testosterone deficient men over 4 months. Methods This Phase IV, randomized, open-label clinical trial was performed on 39 symptomatic, testosterone deficient (TD) men with at least two serum testosterone levels below 300 ng/dL drawn before 10AM. Men were randomized (1:1) to receive either nasal gel three times per day (5.5mg per nostril) and intramuscular TC (200mg) once every two weeks. The primary outcomes were changes in Hematocrit and serum T before and after four months. Secondary outcomes were changes in estradiol (E), PSA and 17-OHP. Data analysis was performed using two-sample and single-sample T tests (Microsoft Excel v.16.60). Results A total of 39 men with testosterone deficiency were randomized to receive either NT (n=15) or TC (n=24). The median participant age was 46 years old with a mean serum T of 237.1 ng/dL and hematocrit of 43.3%. Prevalence of participants who screened positive for OSA on STOP-BANG questionnaire for NT and TC group were 67% and 71%, respectively. Compared to their respective baselines, men in both groups saw significantly increased serum testosterone levels (p 52%) after 4 months was 0% in NT group and 4.2% in TC. Those taking TC saw increases in E (p=0.003) and decreases in 17-OHP (p<0.001) at follow-up, where NT saw no changes. Neither regimen significantly impacted PSA at follow-up. Conclusions Both Intranasal and Intramuscular testosterone regimens are effective in treating hypogonadal men. However, short-acting nasal T does not appear to impact hematocrit levels especially when compared to testosterone cypionate. Those who are at increased risk of developing polycythemia or want to avoid changes in their E or 17-OHP levels may benefit from short-acting T formulations. Disclosure Yes, this is sponsored by industry/sponsor: Acerus Pharmaceuticals Clarification Industry funding only - investigator initiated and executed study Any of the authors act as a consultant, employee or shareholder of an industry for: Acerus Pharmaceuticals