ESPE Abstracts

Objective: In boys during puberty who were undergoing recombinant human growth hormone (rhGH) treatment, we compared the therapeutic efficacy and any adverse reactions, of co-therapy with letrozole/gonadotropin releasing hormone analog (GnRHa).

Methods: Fifty-six pubertal growth hormone deficiency (GHD) boys were studied, they were treated with the combination of letrozole and rhGH (letrozole group) or GnRHa and rhGH (GnRHa group) for at least one year. 35 patients attained adult height (AH).

Results: The increase in height of the letrozole group was significantly more than the GnRHa group, however, there was no significant group difference in the advancement of bone age (BA) (P>0.05). The mean AH in two groups were similar, but the treatment duration of the letrozole was significantly less than GnRHa (P<0.05). There was a significant body mass index (BMI) increase in the letrozle vs GnRHa groups. Of concern, bone mineral density (BMD) decreased in both groups after treatment, but more so in the letrozole cohort.

Conclusion: The combination of letrozole/rhGH in pubertal GHD boys was similar to GnRHa/rhGH in terms of the progression of BA and AH, but the former co-therapy required less treatment time. Disconcerningly, however, this combination may adversely affect BMI and BMD.