Nevirapine, Didanosine, and Zidovudine for Patients With HIV: The INCAS Trial

To the Editor: After review of the Italy, Netherlands, Canada, and Australia (INCAS) trial, we believe that some of the data presentation is confusing and possibly in error.¹ Table 1 reports that 37 patients completed 52 weeks in the 3-drug arm. The text of the "Virologic Effect" section and Figure 2 both report that 51% of these patients had plasma human immunodeficiency virus (HIV) RNA levels of less than 20 copies/mL at 52 weeks. We calculate that 51% of 37 is 19 patients. However, Table 3 reports that 18 of 40 patients in the same group had plasma HIV RNA suppression to less than 20 copies/mL throughout the entire period spanning weeks 40 to 52. If such is the case, there is a discrepancy between the number of patients in the triple-drug arm evaluable at 52 weeks, ie, 37 vs 40 patients. Presuming the correct number to be a total of 40 and presuming that 19 of these patients had plasma HIV RNA levels of less than 20 copies/mL at week 52, the correct value for maximal suppression at week 52 is actually 47.5%, not 51%. (Similar discrepancies exist between Tables 1 and 3 for patients completing 52 weeks in groups 1 and 2.)