Off-label treatment with Imbruvica (ibrutinib), a treatment for lymphoma and leukemia, may reduce anemia and peripheral symptoms of cold agglutinin disease (CAD), according to a preliminary study.
The study, “Effective treatment of cold agglutinin disease / cold agglutinin syndrome with ibrutinib: an international case series, ”Was on display at the 62nd Annual Meeting and Exhibition of the American Society of Hematology (ASH), which was held virtually December 5-8.
Coronary artery disease, also known as cold agglutinin-mediated autoimmune hemolytic anemia (cAIHA), is a rare autoimmune disease in which exposure to cold temperatures causes the binding and premature destruction of blood cells. red (hemolysis).
Among other symptoms, ruptured red blood cells lead to anemia and discoloration of the extremities due to poor circulation, a condition called acrocyanosis.
A reference the treatment of patients with coronary artery disease who have severe anemia or acrocyanosis is rituximab, which targets cells of the immune system responsible for producing antibodies. About half of patients respond to this treatment, but responses usually last less than a year. Although rituximab combination therapy has a longer duration of response, it also carries a risk of long-term unwanted side effects.
Additionally, treatments that suppress the complement system, part of the immune system that is overactive in coronary artery disease, have shown promise in reducing hemolysis, but not peripheral symptoms like acrocyanosis.
International guidelines published earlier this year recommend improper use of Imbruvica for patients with coronary artery disease who do not respond to other conventional treatments. Imbruvica belongs to a class of medicines called Bruton’s tyrosine kinase (BTK) inhibitors and causes the death of antibody-producing cells.
An international team of researchers now set out to evaluate the efficacy of Imbruvica as a treatment for anemia, hemolysis and acrocyanosis in patients with coronary artery disease.
the retrospective study included 10 patients, most of whom had coronary artery disease secondary to another blood disorder, in five centers in Italy, Norway, the United States and the United Kingdom. The patients were aged 55 to 81 and were followed from April 2014 to June 2020, with a median follow-up time of 20 months.
With the exception of one patient who received Imbruvica to treat leukemia, all other people received treatment for coronary artery disease. Also all but two had received a different drug before Imbruvica and the median number of previous treatments was two.
At the time of initiation of treatment, all patients had anemia, seven needed regular blood transfusions, and seven had acrocyanosis.
Treatment with Imbruvica increased levels of hemoglobin (the protein that carries oxygen in red blood cells) in all patients, with a median increase of 4.4 g / dL. Levels of lactate dehydrogenase and bilirubin, two markers of hemolysis, were also decreased in nine of 10 patients.
In particular, all patients who required regular transfusions obtained their transfusion independence, two of whom did so in the first month. In addition, all seven patients with acrocyanosis improved and five saw their symptoms completely resolved. No serious side effects were observed.
While the study is ongoing, these preliminary data suggest that Imbruvica and other BTK inhibitors may be effective in treating coronary artery disease.