How does PrEP work in the real life?

Dear Editor,

We read with interest the article "Pre-exposure prophylaxis programme in Madrid Region: two years of experience".¹ The authors carried out an exhaustive analysis of a group of patients included in the post-exposure prophylaxis programme, and the value of their work cannot be questioned in view of the large number of patients and variables included. However, we felt it was missing the analysis of patients who may have had to discontinue treatment for different reasons. It would be interesting to know how many patients were diagnosed with HIV during the treatment, how many suffered deterioration of renal function and, lastly, to have data on adherence. Landovitz et al.² reported a marked decrease in adherence from 96% to 74% during the first three years in the daily treatment group. While there are no doubts about the benefits of PrEP, other data may be needed to better profile the group of patients most likely to reap those benefits.