Gilead Sciences, Inc. has announced that the Scottish Medicines Consortium (SMC) has approved Zydelig (idelalisib) – a new oral treatment – for adult patients with chronic lymphocytic leukaemia (CLL). Idelalisib has been approved for use within NHS Scotland in combination with rituximab for the treatment of adult patients with relapsed CLL who are unsuitable for chemotherapy and treatment naïve patients with 17p deletion or TP53 mutation who are unsuitable for chemo-immunotherapy.
This decision follows the European Commission granting Marketing Authorisation for idelalisib for the treatment of two incurable blood cancers, CLL and double refractory follicular lymphoma (FL) in the European Union, on 19 September 2014.
Dr Angus Broom, Consultant Haematologist, Western General Hospital, NHS Lothian said: “The SMC’s decision on idelalisib marks a significant advance for patients with CLL in Scotland, as it is a life-extending treatment with the potential to help alleviate both the emotional and physical impact for patients and families living with CLL. Idelalisib provides physicians with a new treatment option for previously untreated patients with markers of aggressive CLL disease or relapsed CLL.”
Approximately 3,200 individuals are diagnosed with CLL in the UK each year.1 CLL is usually a slow growing incurable blood cancer2 that can lead to life-threatening complications, such as anaemia, serious infection and bone marrow failure requiring treatment.3, 4 The goal of therapy for patients with this form of cancer is to improve overall survival and quality of life.5 Chemo-immunotherapy is initially used to treat CLL, however patients eventually relapse and many cannot tolerate the side effects associated with chemo-immunotherapy. Additionally, some patients have genetic alterations in their CLL cells. Deletion of part of chromosome 17 – del (17p) – or a mutation in the TP53 gene in CLL cells have been linked to poor prognosis, being predictive of more rapid disease progression. For these patients most conventional chemo-immunotherapy treatments are not effective and deliver poor responses with relatively short duration.6
The SMC’s decision on idelalisib for the treatment of CLL is supported primarily by data from a randomised, placebo-controlled Phase 3 trial (Study 116)7 of idelalisib plus rituximab versus placebo plus rituximab in 220 patients with relapsed CLL who were not able to tolerate standard chemotherapy. Study 116 was stopped early in October 2013 by an independent Data Monitoring Committee due to a statistically significant difference in progression-free survival (PFS) in the idelalisib arm compared with the rituximab only treatment arm (events 14.5% vs. 53.6% hazard ratio = 0.18 (95 percent CI: 0.10, 0.32), p<0.0001). Patients in this study were eligible to continue receiving idelalisib therapy in an open-label extension study (Study 117). Results from the primary and the extension study show that among the 110 patients randomised to receive idelalisib plus rituximab, the median PFS has now been reached, and is 19.4 months8 (placebo plus rituximab media PFS is 7.3 months).8 Idelalisib plus rituximab was similarly effective in patients with del (17p) and/or TP53 mutation.9
1 Cancer Research UK. Chronic Lymphocytic Leukaemia (CLL) risks and causes. Available at http://www.cancerresearchuk.org/about-cancer/type/cll/about/chronic-lymphocytic-leukaemia-risks-and-causes. Accessed January 14, 2015.
2 Redaelli A, et al. The clinical and epidemiological burden of chronic lymphocytic leukaemia. Eur J Cancer Care (Engl) 2004;13:279-287.
3 National Cancer Institute(NCI). Chronic lymphocytic leukemia treatment (PDQ). National Cancer Institute (NCI). Available at http://www.cancer.gov/cancertopics/pdq/treatment/CLL/Patient/page1/allpages Accessed September, 2014.
4 National Cancer Institute(NCI). What you need to know about non-Hodgkin lymphoma. Available at http://www.cancer.gov/cancertopics/wyntk/non-hodgkin-lymphoma.pdf Accessed September, 2014.
5 Shanafelt TD & Kay NE. Comprehensive management of the CLL patient: a holistic approach. Hematology Am Soc Hematol Educ Program 2007:324-331.
6 Seiffert M et al. Exploiting biological diversity and genomic aberrations in chronic lymphocytic leukemia. Leuk Lymphoma 2012; 53:1023-1031.
7 Furman RR et al. Idelalisib and rituximab in relapsed chronic lymphocytic leukemia. N Engl J Med 2014; 370:997-1007.
8 Sharman JP et al. Second Interim Analysis of a Phase 3 Study of Idelalisib (ZYDELIG) Plus Rituximab (R) for Relapsed Chronic Lymphocytic Leukemia (CLL): Efficacy Analysis in Patient Subpopulations with Del(17p) and Other Adverse Prognostic Factors. [ASH abstract 330; Session 642; Date: December 8, 2014; Time: 08:15].
9 Furman RR et al. Supplementary Appendix. Idelalisib and rituximab in relapsed chronic lymphocytic leukemia. N Engl J Med 2014; DOI: 10.1056/NEJMoa1315226
10 Zydelig Summary of Product Characteristics (100 & 150mg film-coated tablets) – September 2014.
Source: Gilead Sciences