Experience in applying pharmacoeconomic modeling using a "decision tree" to determine the volume and cost structure of Hodgkin's lymphoma treatment in HIV-positive and HIV-negative patients

The presence of infection caused by the human immunodeficiency virus increases the risk of developing oncological diseases, aggravates the course and worsens their prognosis as a comorbid condition. The probability of developing Hodgkin's lymphoma in patients infected with the human immunodeficiency virus is 3-10 times higher than in the general population, while against the background of taking antiretroviral therapy, the risk of developing Hodgkin's lymphoma increases 20-30 times. It would be logical to assume an increase in the burden of medical expenses in this category of patients compared with patients suffering from oncological diseases without concomitant infection caused by the human immunodeficiency virus. Unfortunately, despite of a number of studies, the subject matter of determining the volume and structure of costs, their comparative pharmacoeconomic assessment of Hodgkin's lymphoma treatment in patients with infection caused by the human immunodeficiency virus, and without it, has not been largely disclosed. The aim of the study is to determine the volume and cost structure for the treatment of patients with Hodgkin's lymphoma from two groups: those associated with the human immunodeficiency virus and those without it, who underwent therapy at A.S. Loginov Moscow Clinical Research Center under Moscow Healthcare Department using pharmacoeconomic modeling using the "decision tree" method. Materials and methods. To calculate the cost, we used a restrospective group of patients who received treatment at A.S. Loginov Moscow Clinical Research Center from June 2015 to December 2023 within the framework of clinical recommendations applied as of 2024. All patients were over 18 years old. The sample size was 67 people, 34 patients with Hodgkin's lymphoma associated with the human immunodeficiency virus, 33 with a negative status for the human immunodeficiency virus. The formed sample was tested using tests of matched pair analysis: Mann–Whitney, Fisher, Wilcoxon, c2 ones, which confirmed randomness of selected groups. To determine the costs, pharmacoeconomic modeling using a "decision tree", technological maps to the price list of a medical organization minus the marginal surcharge, marginal selling prices for life-saving medications and for other drugs according to the purchase prices of government contracts in 2024 were used. To calculate the median and the average cost values, the stages of primary diagnosis, assessment of remission status using positron emission tomography (CT), courses of polychemotherapy, targeted drugs, and autologous hematopoietic stem cell transplantation were taken into account. To calculate the need for medicines, the median body surface area and the weight of the patients from the sample were used: 1.85 m2 and 70.9 kg. Results. In the group of patients with Hodgkin's lymphoma without concomitant infection caused by the human immunodeficiency virus, the median cost of treatment, including primary diagnosis, was 584,641 rubles, in case of therapy complications the median cost was 3,935,167 rubles, the median cost of radiation therapy was 260,800 rubles. In the group of patients with Hodgkin's lymphoma and the course of infection caused by the human immunodeficiency virus, the median cost of treatment was 440,616 rubles without complications, in case of intensification of therapy aimed at treating complications – 1,020,332 rubles, radiation therapy was not performed in these patients. The average cost of diagnosis and treatment per one patient in both groups: 1,017,038 rubles without complications for patients with Hodgkin's lymphoma without concomitant infection caused by the human immunodeficiency virus, 3,578,882 rubles for the same group with complications; in the group of Hodgkin's lymphoma associated with infection caused by the human immunodeficiency virus, without complications – 852,010 rubles, that with complications – 2,416,962 rubles. Conclusions. Pharmacoeconomic modeling using a "decision tree" is one of the simplest and most accessible pharmacoeconomic tools that give the opportunity to calculate the average and the median costs of treating patients with oncohematological disease and comorbid pathology affecting the prognosis. Additional information about the clinical and economic effectiveness of the treatment method is provided by conducting a pharmacoeconomic analysis with calculating clinical indicators and determining the cost of an efficiency unit. Conducting a pharmacoeconomic analysis enables to better understand the factors that influenced the increase in costs and identify the ways to optimize them.