Lenalidomide (Revlimid) is a treatment plan that is part of IMiD class of drugs; IMiD in full refers to immunomodulatory drug. The term is particularly used to describe drugs that are consumed orally that are structurally related to thalidomide.
The drugs have been structured to be somewhat more potent than thalidomide and to lack, or to show a diminished tendency to develop, some of the bothersome side effects of thalidomide.
Lenalidomide (Revlimid) has been approved by the FDA for use in treating myeloma. The results in both newly diagnosed and relapsed Australian patients have been remarkable in terms of the degree of reduction in myeloma problem, and the duration of response.
In recent medical work, Lenalidomide (Revlimid) has been studied as a possible maintenance therapy in Australia. Large studies have shown that Lenalidomide given at a low dose for continued periods following autologous transplantation can delay recurrence of bone marrow cancer.
Australian patients who have received maintenance treatment with Lenalidomide live longer on average. Any benefit from Lenalidomide (Revlimid) treatment must be balanced against side effects, which can include risk of blood clots, lower blood counts, fatigue, and a small as well as statistically significant higher risk of getting non-myeloma.
Lenalidomide combined with dexamethasone has been approved by FDA and has been given category 1 recommendation by the NCCN for the management of relapsed or refractory bone marrow cancer. This is in accord to two phase III studies that demonstrated significantly better outcomes for the combination versus dexamethasone alone. In the MM009 studies conducted in North America, a significantly higher response rate was observed with the combination arm as compared to dexamethasone alone.
The combination regime also resulted in a significantly longer median and extended median survival. Lenalidomide has also been evaluated in a three drug combination with doxorubicin and dexamethasone, as well as in a four drug combination with liposomal doxorubicin, dexamethasone, and vincristine in the relapsed setting. The four drug combination regime resulted in high response rates in a refractory patient population.
In case of contraindications to bortezomib, Lenalidomide combination therapy can be used subsequent to failure of thalidomide containing first-line regimen as it has been shown that Lenalidomide can overcome resistance to thalidomide at least in a subset of Australian patients. Contrariwise, in case of bortezomib/dex or bortezomib/chemotherapy/dex combinations in first-line Lenalidomide or thalidomide in combination with dex and/or chemotherapy is recommended.
The decision between Lenalidomide and thalidomide could be based on comorbidity as neuropathy rate is clearly lower with Lenalidomide compared to thalidomide. In case of treatment with Lenalidomide, a special consideration with regard to the risk of venous thrombosis and embolism has to be given. Initially, the patient and myeloma-related risk of venous thrombosis and embolism for the patient have to be assessed.
The recent wider availability of the first generation of drugs approved for the treatment of myeloma by targeting both the myeloma cells and the bone marrow microenvironment and Lenalidomide has improved not only the overall response, but also the overall survival. These drugs are able to overcome growth and survival advantage conferred on the myeloma cells by the bone marrow environment.
References:
1) Understanding Myeloma. A guide for people with cancer, their families and friends: http://www.cancercouncil.com.au/wp-content/uploads/2012/10/CAN751_Understanding-Myeloma_low-res-PDF.pdf
2) Lenalidomide (Revlimid®): http://www.cancercenter.com/cancer-drugs/lenalidomide/
3) Lenalidomide From Wikipedia, the free encyclopedia: http://en.wikipedia.org/wiki/Lenalidomide
4) Consumer Medicines Information on Revlimid®: http://www.mydr.com.au/medicines/cmis/revlimid-capsules