Hydroxyurea mobile directly observed therapy versus standard monitoring in patients with sickle cell anemia: a phase 2 randomized trial

Sickle cell anemia (SCA) prevalence remains high in sub-Saharan Africa. Long-term treatment with hydroxyurea (HU) increases survival, however, poor adherence to treatment could limit effectiveness. Whilst HU treatment adherence is currently high, this might decrease over time. We conducted a single-center, randomized, open-label, parallel group phase 2 controlled clinical trial to determine whether mobile Directly Observed Therapy (m-DOT) increases HU treatment adherence (NCT02844673). Eligible participants were adults with homozygous SCA. People on a chronic blood transfusion program, with hemoglobin (Hb) A levels greater than 20% of the total Hb, total Hb less than 4 g/dL, pregnant or HIV positive were excluded. After a 3-month pre-treatment period participants were randomized to either m-DOT or standard monitoring arm. All participants received smart mobile phones and were treated with HU (15 mg/kg) daily for three months. In the m-DOT arm, drug intake was video recorded on cell phone by the participant and the video sent to the study team. The primary objective was to evaluate the effect of m-DOT on adherence to HU treatment by medication possession ratio (MPR). Of the 86 participants randomized, 76 completed the trial (26.13 ± 6.97 years, 63.5 % female). Adherence was high (MPR > 95 %) in both groups, 29 (80.6 %) in m-DOT versus 37 (94.9 %) in the standard monitoring arm (P = 0.079). No HU treatment was withheld from participants due to safety concerns. m-DOT did not increase adherence to HU treatment. We recommend that further testing in larger trials with a longer follow up period be undertaken. Sickle cell anemia (SCA) is an inherited blood disorder in which there is an abnormal protein inside red blood cells. This results in red blood cells becoming sickle shaped and more easily destroyed in the body. Long-term treatment with hydroxyurea can reduce the frequency of illness and hospitalization. However, often people do not manage to take their medication regularly when treatment is long-term. We therefore investigated whether people with SCA in sub-Saharan Africa are more likely to take hydroxyurea when they are remotely monitored than when they are not. Remote monitoring did not improve adherence. However, our study is small and was undertaken over a short time period when hydroxyurea had only recently become available to people with SCA. We propose further studies, to see if remote monitoring increases medication adherence in people with SCA in other scenarios. Sasi et al. evaluate whether using a smartphone to record drug treatment improves monitoring of adherence to medication and improved treatment outcome. In a pilot study of sickle cell anemia in patients starting long-term treatment with hydroxyurea, adherence was not increased when mobile Directly Observed Therapy (m-DOT) was used.