The U.S. Food and Drug Administration (FDA) yesterday in a press release informed about the approval of Imbruvica (ibrutinib) for the treatment of adult patients with chronic graft versus host disease (cGVHD) who have previously failed with one or more treatment. This is the first drug that the FDA has given its approval to in this disease condition.
Patients may develop chronic GVHD which may become life threatening after they have received a stem cell transplant from bone marrow or blood. This type of stem cell transplant is called hematopoietic stem cell transplantation (HSCT) and is used in some types of blood and bone marrow cancers. These transplanted cells are treated a foreign by the body and the cells from this transplant in turn attack the healthy cells of the patient. Around one third to three fourths of all patients given HSCT may develop chronic GVHD. This condition affects the skin, eyes, liver, lungs, mouth and gut.
Richard Pazdur, director of the FDA’s Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research said in the release that this treatment with ibrutinib would be useful for patients who have not responded to other therapies. This is the first time these patients would have a treatment option he added. This drug that has been approved for cancer treatment before has now found a new use in treatment of this “serious and life-threatening condition” that affects people with blood cancer who have received a bone marrow transplant he explained.
For this approval, the manufacturers had submitted its effectiveness report as studied in a clinical trial involving 42 patients of chronic GVHD who were all treated with Imbruvica. These patients were all nonresponsive to existing treatment for GVHD. They had a variety of symptoms including skin rashes, mouth ulcers and organ damage. Half of the patients had two or more damaged organs due to chronic GVHD. Results showed that on treatment with Imbruvica, 67% showed improvement in their symptoms and in nearly half of the patients (48%) the improvements persisted for up to five months or longer.
Imbruvica is a primarily anticancer drug that works by inhibiting kinases and is approved for use in chronic lymphocytic leukemia (CLL), Waldenström’s macroglobulinemia and marginal zone lymphoma.
Some of the commonly reported side effects with Imbruvica included bruising, tiredness, diarrhea, and reduction of blood platelet counts and risk of bleeding, swellings, muscle aches, ulcers or sores in the mouth, pneumonias, anemia and nausea. Severe bleeding, infections and irregular heartbeats were some of the more concerning side effects. There is also a risk of developing secondary cancers or new cancers. The drug is not approved for pregnant and breastfeeding mothers as it can harm the fetus or the breastfeeding baby.
Imbruvica received an orphan drug status with the FDA that allowed it incentives which would encourage its development in rare diseases. The approval was granted to Pharmacyclics LLC.
Graft Versus Host Disease (GVHD)
Graft versus host disease or GVHD is a condition that may occur after a person has had an transplant. The donated bone marrow or the blood cells that come from the donor are perceived as foreign by the body cells and vice versa. The donated bone marrow cells thus turn upon the patient cells and begin attacking. It can be broadly classified into two – acute and chronic GVHD.
A transplant recipient may experience both forms of GVHD or may be completely spared of either form. Treatment for acute GVHD is usually with drugs that suppress the immunity or immunosupressants and corticosteroids.
Chronic GVHD is a later phase of the acute form or may be a separate disease entity altogether. Chronic GVHD is usually seem among patients who receive blood cells, stem cells or bone marrow from a donor who is not a match. It can begin any time after the transplant – sometimes several years later. Chronic GVHD skin, eyes, mouth, liver, lungs, neuromuscular system, gastrointestinal system or urinary tract. Diagnosis is usually made with a physical examination and biopsy of the affected sites. Treatment options for GVHD include immunosuppressive medications, steroids etc.