The context

Stem cell/bone marrow transplantation is an effective treatment for aplastic anaemia (AA) but does involve risk. The degree of risk has been shown to depend on the source of donor stem cells. Sibling donors with identical tissue type offer the lowest risk. There is only a 1 in 4 chance of having a sibling with identical tissue type, so this option is not available to many. In recent years, improvements have been made in using haploidentical family donors, meaning family members with half-matched tissue type. All parents and 1 in 2 siblings are half-matched, meaning the chances of finding a suitable haploidentical donor within the family are higher. We need to understand when haploidentical stem cell transplant (HID-HSCT) should be offered to individuals with AA.

The study

The authors looked back over the experiences of 55 individuals aged 14-30 with severe AA. They compared those who had received immunosuppressive therapy (a standard first line treatment involving ATG and ciclosporin) with those who had received HID-HSCT. This was not a clinical trial, so groups were not deliberately matched to minimise bias.

The outcome

With HID-HSCT, remission was achieved within 3 months and nobody relapsed. For every 10 individuals receiving HID-HSCT, treatment success rate was 80%. With immunosuppressive therapy (IST), remission was slower, taking more than a year to achieve full effect. For every 10 patients receiving IST, again, treatment success was 80%. HID-HSCT involved a much longer hospital stay (62 days for HID-HSCT versus 28 days for IST).

Conclusion

HID-HSCT was an effective treatment for AA in this group. Overall outcomes from HID-HSCT were similar to those from IST. Further studies are needed to look at HID-HSCT in a clinical trial.

Information source: Therapies for non-severe, transfusion-dependent aplastic anaemia. Lin S, et al. Hangzhou, China.

Summary kindly provided by Dr Laura Jardine, National Institute of Health Research Clinical Lecturer in Haematology, Newcastle University