Sprycel is a multiply-targeted tyrosine kinase inhibitor. Tyrosine kinases affect systems of cellular division and survival, and are frequently over-expressed or abnormally active in cancer cells. By targeting these systems, Sprycel is designed to reduce the growth and viability of various types of cancer.
Sprycel is specifically indicated to treat adults with chronic, accelerated, or myeloid or lymphoid blast phase chronic myeloid leukemia (CML) with resistance or intolerance to prior therapy including imatinib. It is also indicated for the treatment of Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) with resistance or intolerance to prior therapy.
Sprycel is supplied as a white to off-white, biconvex, film-coated tablet designed for oral administration. The recommended initial dosing of Sprycel is 70 mg twice daily with or without food. Incremental dose increase or decrease (in 20 mg steps) is recommended based on individual safety and tolerability.
Approval of Sprycel was based on four single-arm multicenter studies which investigated the safety and efficacy of the drug in treating imatinib-resistant or imatinib-intolerant CML and Ph+ ALL. In all four trials, subjects received 70 mg Sprycel twice daily. These trials were all ongoing at the time of approval. The four studies each investigated the drug in the treatment of a single disease subclass.
Chronic Phase CML Study
This trial enrolled 186 patients with imatinib resistant (68%) or intolerant (32%) chronic-phase CML. Subjects received treatment for a median of 5.6 months (range: 0.03 to 8.3 months). Results yielded efficacy in the trial's primary endpoint, with Sprycel producing major cytogenetic response (MCyR) in 45% of subjects, including complete cytogenic response (CCyR, defined as 0% Ph+ cells detected) in 33% of subjects. Further, complete hematologic response (CHR) was achieved in 90% of subjects.
Accelerated Phase CML Study
This trial enrolled 107 patients with imatinib resistant (93%) or intolerant (7%) accelerated-phase CML. Subjects received treatment for a median of 5.5 months (range: 0.2 to 10.1 months). Results yielded efficacy in the trial's primary endpoint, with Sprycel producing major hematologic response (MaHR) in 59% of subjects, including CHR in 33% of subjects and no evidence of leukemia (NEL) in 26% of subjects. In addition, MCyR was achieved in 31% of subjects, including CCyR in 21% of subjects.
Myeloid Blast Phase CML Study
This trial enrolled 74 patients with imatinib resistant (92%) or intolerant (8%) myeloid-blast-phase CML. Subjects received treatment for a median of 3.5 months (range: 0.03 to 9.2 months). Results yielded efficacy in the trial's primary endpoint, with Sprycel producing MaHR in 32% of subjects, including CHR in 24% of subjects and NEL in 8% of subjects. In addition, MCyR was achieved in 30% of subjects, including CCyR in 27% of subjects.
Lymphoid Blast Phase CML/Ph+ ALL Study
This trial enrolled 42 patients with imatinib resistant (92%) or intolerant (8%) lymphoid-blast-phase CML, and 36 patients with imatinib resistant (94%) or intolerant (6%) Ph+ ALL. CML subjects received treatment for a median of 2.8 months (range: 0.1 to 6.4 months), and Ph+ ALL subjects received treatment for a median of 3.2 months (range: 0.2 to 8.1 months). Results yielded efficacy in the trial's primary endpoint, with Sprycel producing MaHR in 31% of CML subjects and 42% of Ph+ ALL subjects, including CHR in 26% and 31% of subjects and NEL in 5% and 11% of subjects, respectively. In addition, MCyR was achieved in 50% and 58% of subjects, including CCyR in 58% and 58% of subjects.
Ongoing Study Commitments
Adverse events associated with the use of Sprycel may include, but are not limited to, the following:
Myelosuppression was commonly reported, including serious or severe neutropenia, thrombocytopenia, and anemia. The rate of myelosuppression was higher in patients with accelerated phase or myeloid blast phase CML or lymphoid blast phase Ph+ ALL than in patients with chronic phase CML.
The effectiveness of Sprycel may be affected by concomitant administration of other drugs:
Sprycel is believed to bind to multiple conformations of ABL kinase. It has been shown to inhibit multiple tyrosine kinases at nanomolar concentrations, including BCR-ABL, SRC family (SRC, LCK, YES, FYN), c-KIT, EPHA2, and PDGFRß.
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For additional information regarding Sprycel or CML and Ph+ ALL, please visit the Sprycel web page.