Home > Article > Luspatercept for Beta-thalassemia – A New Horizon?
Haematology
Read Time: 3 mins

Luspatercept for Beta-thalassemia – A New Horizon?

Published Online: May 15th 2020 European Oncology & Haematology. 2020;16(1):16-7 DOI: https://doi.org/10.17925/EOH.2020.16.1.16
Authors: Mohammad Ammad Ud Din, Faiz Anwer
Quick Links:
Abstract
Article
Article Information
Abstract:
Overview

Several treatment options are being explored to reduce the transfusion burden and improve the quality of life in patients with beta-thalassemia. One such prospect is the drug luspatercept, which has recently been approved for use in the USA for treatment of beta-thalassemia. However, socioeconomic factors may act as a barrier to its widespread use.

Keywords

Thalassemia, beta-thalassemia, Cooley’s anaemia, luspatercept, microcytaemia, thalassemia major

Article:

The chronic anaemia of beta-thalassemia major (b-thal) results from defective erythropoiesis secondary to a genetic defect in haemoglobin synthesis.1 Consequently, patients with
moderate-to-severe disease rely on blood transfusions to maintain an adequate level of haemoglobin.2 Over time, this causes an iron-overloaded state, in addition to the possible
blood-borne infections resulting from repeated transfusions.3 The widespread use of iron chelators has greatly improved the quality and lifespan of patients with b-thal and in recent years many advancements have been made in an attempt to reduce the dependency on blood transfusions for treatment. Some of the noteworthy lines of treatments that have received consideration in the last decade include gene therapy, allogeneic haematopoietic stem cell transplantation and pharmacological agents such as luspatercept.4

Luspatercept is a recombinant fusion protein with a modified extracellular domain of the human activin receptor type IIB, joined to the fragment crystallisable domain of human immunoglobulin G1, which attaches to a subset of transforming growth factor beta superfamily ligands, leading to complex downstream signalling pathways, resulting in increased erythropoiesis.5 The US Food and Drug Administration (FDA) first approved luspatercept for the treatment of anaemia in
transfusion-dependent adults with b-thal in the USA in November 2019,6 based on the results of the phase III BELIEVE trial (ClinicalTrials.gov Identifier: NCT02604433), which showed that the use of luspatercept resulted in a significant decrease in the need for packed red blood-cell (pRBC) transfusions.7

The large-scale double-blind trial was performed in over 60 centres across 15 countries and included pRBC transfusion-dependent patients with confirmed b-thal over the age of 18 years. The median age of the cohort was 30 years. These patients were randomised 2:1 to receive
1.0 mg/kg luspatercept subcutaneously, which was titrated up to 1.25 mg/kg, or placebo (n=224 and n=112, respectively) every 3 weeks for at least 48 weeks. All patients also continued to receive transfusions and iron chelation therapy. Of the patients in the treatment arm, 21.4% reached the study’s primary endpoint of ≥33% reduction in transfusion burden plus a reduction of ≥2 pRBC units during weeks 13–24, compared to a 12-week baseline period, versus 4.5% of patients in the placebo arm (odds ratio 5.79; p<0.0001). Furthermore, 70.5% of the patients in the treatment group achieved a ≥33% reduction in transfusion burden during any consecutive 12 weeks of treatment. In comparison, only 29.5% of patients in the placebo group achieved the same result (p<0.001).

Adverse events (AEs) were generally mild and tolerated, with grade 3 or higher AEs occurring 29.1% of patients treated with luspatercept and 15.6% of patients in the placebo group.
The most common grade 3 or higher AEs were anaemia (3.1% versus 0%), increased liver iron concentration (2.7% versus 0.9%) and hyperuricaemia (2.7% versus 0%) in the luspatercept and the placebo groups, respectively. Other commonly seen AEs in >5% of patients in the treatment group included bone pain, arthralgias, hypertension and dizziness. Most of these symptoms were controlled with medications, although permanent discontinuation of treatment because of an AE was required in 5.4% of patients treated with luspatercept because of arthralgias, back and bone pain. Dose reductions were required in 2.7% of patients, most frequently because of hypertension and headache.8 Thromboembolic events were seen in 3.6% of patients in the luspatercept group and 0.9% of patients in the placebo group. All of these events occurred in patients with a history of splenectomy as well as at least one more risk factor for thromboembolic events at baseline.7

By decreasing the transfusion burden, luspatercept presents an exciting option that could improve quality of life for patients with b-thal; however, the cost of the drug is substantially higher than the standard therapy and the need for continuous therapy would likely increase the cost of b-thal management.9 This is an important factor, as in developing countries in South Asia, the prevalence of the disease is fairly high due to the high genetic prevalence and the common practice of consanguineous marriages.10 Also, with novel treatment alternatives under development, such as gene therapy and stem cell transplant,11,12 which would potentially eliminate the need for erythropoiesis-stimulating agents, the role of luspatercept in the context of such therapies might be minimal. Therefore, despite all its merits, the cost of luspatercept can be a barrier to treatment for patients with b-thal in areas of high prevalence. Clinical trials investigating the long-term safety profile of the drug, as well as its use in non-transfusion dependent patients with b-thal minor, are currently ongoing (i.e., the BEYOND trial [ClinicalTrials.gov identifier: NCT03342404] and a study to evaluate long-term safety in subjects who have participated in other luspatercept clinical trials [ClinicalTrials.gov identifier: NCT04064060).8

Article Information:
Disclosure

Mohammad Ammad Ud Din and Faiz Anwer have nothing to declare in relation to this article.

Compliance With Ethics

This article is an opinion piece and does not report on new clinical data, or any studies with human or animal subjects performed by any of the authors.

Review Process

Double-blind peer review.

Authorship

The named authors meet the International Committee of Medical Journal Editors (ICMJE) criteria for authorship of this manuscript, take responsibility for the integrity of the work as a whole, and have given final approval for the version to be published.

Correspondence

Mohammad Ammad Ud Din, Internal Medicine Department, Rochester General Hospital, 1425 Portland Avenue, Rochester, NY, USA 14621. E: [email protected]

Support

No funding was received in the publication of this article.

Open Access

This article is freely accessible at touchONCOLOGY.com © Touch Medical Media 2020.

Received

2020-04-11

References

  1. Higgs DR, Thein SL, Woods WG. The molecular pathology of the thalassaemias. In: Weatherall DJ, Clegg B, eds. The Thalassaemia Syndromes. 4th edn., Oxford: Blackwell Science, 2001;133–91.
  2. Chonat S, Quinn CT. Current standards of care and long term outcomes for thalassemia and sickle cell disease. Adv Exp Med Biol. 2017;1013:59–87.
  3. Rund D, Rachmilewitz E. β-Thalassemia. N Engl J Med. 2005;353:1135–46.
  4. Fibach E, Rachmilewitz EA. Pathophysiology and treatment of patients with beta-thalassemia – an update. F1000Res. 2017;6:2156.
  5. Suragani RN, Cadena SM, Cawley SM, et al. Transforming growth factor-β superfamily ligand trap ACE-536 corrects anemia by promoting late-stage erythropoiesis. Nat Med. 2014;20:408–14.
  6. US Food & Drug Administration. FDA approves first therapy to treat patients with rare blood disorder. 2019. Available at: www.fda.gov/news-events/press-announcements/fda-approves-first-therapy-treat-patients-rare-blood-disorder (accessed 20 April 2020).
  7. Cappellini MD, Viprakasit V, Taher AT, et al. A phase 3 trial of luspatercept in patients with transfusion-dependent β-thalassemia. N Engl J Med. 2020;382:1219–31.
  8. Markham A. Luspatercept: first approval. Drugs. 2020;80:85–90.
  9. Skari C. Reblozyl: ‘BELIEVE’ study in adults with TDT β-thalassaemia. 2020. Available at: https://thalassaemia.org.cy/publications/clinical-trial-updates/luspatercept/ (accessed 20 April 2020).
  10. Saeed U, Piracha ZZ. Thalassemia: impact of consanguineous marriages on most prevalent monogenic disorders of humans. Asian Pac J Trop Dis. 2016;6:837–40.
  11. Finotti A, Breda L, Lederer CW, et al. Recent trends in the gene therapy of β-thalassemia. J Blood Med. 2015;6:69–85.
  12. Srivastava A, Shaji RV. Cure for thalassemia major – from allogeneic hematopoietic stem cell transplantation to gene therapy. Haematologica. 2017;102:214–23.

Further Resources

Related Content In Haematology
  • Copied to clipboard!
    accredited arrow-downarrow_leftarrow-right-bluearrow-right-dark-bluearrow-right-greyarrow-right-orangearrow-right-whitearrow-right-blueavatarcalendarchevron-down crosscrossdownloademailexclaimationfeedbackfiltergraph-arrowinterviewslinkmenumore_dots padlock person play_buttonplay-colour-tmcplay-colourAsset 1podcastprinter scenerysearch share social_facebooksocial_googleplussocial_instagramsocial_linkedin_altsocial_linkedin_altsocial_pinterestlogo-twitter-glyph-32social_youtubeshape-star (1)tick-bluetick-orangetick-whiteticktimetranscriptup-arrowwebinar