Despite many years of clinical use in Hodgkin lymphoma, no previous studies have evaluated the relationship between doxorubicin pharmacokinetics and clinical response. In a pilot study, we associated the area under the curve of doxorubicin with successful remission. Patients with successful remission (n = 14) had a trend toward a higher median area under the curve than those who failed remission (n = 4; 36,390 versus 19,350 ng/mL x minute, P = 0.08, respectively). Median peak serum concentrations were 73 ng/mL among failures and 280 ng/mL in those who achieved remission (P = 0.06). The 2 groups did not differ regarding demographic and clinical parameters or doxorubicin dose. If corroborated by further studies, therapeutic drug monitoring of doxorubicin may be warranted in patients with Hodgkin lymphoma.