LEUKOTAC® in Steroid-Resistant acute Graft-versus-Host Disease

On October 12, 2017, ElsaLys Biotech announced the Company has acquired from JAZZ PHARMACEUTICALS the development and commercialization rights of LEUKOTAC® (inolimomab), a monoclonal antibody that has recently demonstrated its clinical superiority in the treatment of Steroid-Resistant acute Graft-versus-Host Disease (steroid-resistant aGvHD), an orphan disease with very poor prognosis.

GvHD is the main complication of hematopoietic stem cell transplantation, the last treatment option for patients with certain blood cancers and severe immunodeficiency. To date, clinicians have no reliable means to predict the occurrence of GvHD and even less its steroid-resistant form. No treatment has yet obtained marketing authorization in this indication and each year steroid-resistant aGvHD causes almost 4,000 deaths in Europe.

LEUKOTAC® (inolimomab) is an immunotherapy monoclonal antibody that targets the interleukin-2 receptor (IL-2), a chemical molecule named cytokine that contributes to the development and proliferation of some white blood cells including T-cells responsible for aGvHD. By linking specifically to the α chain of the receptor (CD25), LEUKOTAC® prevents IL-2 from binding on the surface of the donor’s over-active T-cells which blocks their multiplication. 
The efficacy of LEUKOTAC® in steroid-resistant aGvHD is primarily due to its specificity and its high affinity for the IL2 receptor, considerably higher than other drugs in the same class. 

LEUKOTAC® was already administrated to nearly 1,200 children and adults with aGvHD, mostly with steroid-resistant aGvHD, whether in clinical trials or for compassionate use. Based on additional analyses of a recent pivotal Phase 3 study conducted in 100 patients with severe with steroid-resistant aGvHD (77% of patients diagnosed grade 3 or 4), LEUKOTAC® has demonstrated very promising results both in terms of efficacy (37% reduction in the risk of death, p=0.055 1-sided and reduction of primary composite endpoint of death at one year without change in treatment 28%, p=0.095 1-sided) and tolerability (significant reduction in adverse events, in particular infectious). All these results were obtained in comparison with a control group receiving anti-thymoglobulin immunosuppressant.

ElsaLys Biotech is now in discussion with the European Medicines Agency (EMA) in order to assess the terms of registration at the earliest opportunity. At the same time, to allow physicians and patients to gain access as quickly as possible to LEUKOTAC®, ELSALYS BIOTECH is currently preparing requests for compassionate use authorization of the drug for patients with severe steroid-resistant aGvHD with the different national health authorities (Named Patient Basis or cohort Temporary Authorization for Use  evaluated in France by the ANSM, the National Agency for Medicines and health products Safety). Discussions with the US Food and Drug Administration (FDA) are expected to start as early as 2018.