# Clinical patterns of thalidomide in the treatment of transfusion-dependent β-thalassaemia in children: a prospective single-arm study in China

## TL;DR

This study examines the long-term effects of thalidomide in children with β-thalassaemia, finding benefits in growth and transfusion needs but also significant risks like neuropathy.

## Contribution

The study provides new insights into the long-term clinical patterns and safety profile of thalidomide in treating transfusion-dependent β-thalassaemia in children.

## Key findings

- Thalidomide showed an 82.9% overall response rate in reducing transfusion needs.
- 64% of patients showed significant improvement in height growth after 12-18 months of treatment.
- Neuropathy and other adverse events limited long-term use of thalidomide in children.

## Abstract

Previous studies in β-thalassaemia have shown that thalidomide is effective in reducing transfusion volume and is safe for short-term therapy of 6 months or less. The aim of this prospective study was to investigate long-term benefits and side effects of thalidomide in the treatment of transfusion-dependent β-thalassaemia (TDT) in children.

We analyzed the data from children and adolescents with TDT enrolled in a single-arm prospective study. The overall response rate, the incidence of discontinuation due to adverse events, the effect on height growth, and the effect on nerve conduction velocity were analyzed when patients received thalidomide for up to 1 year, or until unacceptable toxicity during the extended follow-up. The Kruskal-Wallis H test, one-way ANOVA, the Cochran-Mantel-Haenszel Chi-square test, and others were used for analysis.

The overall response rate was 82.9%. The most common grade 3–4 adverse events were abdominal pain, haemolysis, and leukocytopenia/neutropenia. Of the 73 patients who underwent nerve conduction velocity assessment during treatment for more than 12 months, 12 patients developed polyneuropathy and 26 developed motor neuropathy. The standard deviation scores (SDS) of height in major responders were significantly improved (−1.57, 95% CI (−1.95, −1.18)) at the end of 12 to 18-month treatment (p < 0.001). 64% of patients showed improvement in SDS of height.

Thalidomide is associated with long-term benefits in growth and transfusion burden. A minority of patients required prolonged therapy beyond 6 months to achieve a response. Neuropathy and unexpected adverse events prevent the long-term use of thalidomide in children with thalassaemia and close monitoring is needed. (chictr.org.cn identifiers: ChiCTR2000034998)