Revlimid (lenalidomide) is an oral capsule used to treat several blood cancers and a bone marrow disorder. It is FDA-approved for six specific conditions: multiple myeloma, a type of bone marrow failure called myelodysplastic syndromes (MDS), and three forms of lymphoma. The drug works by boosting the immune system’s ability to attack cancer cells while also cutting off the support structures tumors need to grow.
FDA-Approved Uses
Revlimid is approved for the following conditions in adults:
- Multiple myeloma: Used alongside dexamethasone (a steroid) for active disease, and also used alone as ongoing maintenance therapy after a stem cell transplant.
- Myelodysplastic syndromes (MDS): Specifically for patients who need regular blood transfusions due to anemia linked to a particular genetic change called a deletion 5q abnormality. To qualify, the MDS must be classified as low or intermediate-1 risk.
- Mantle cell lymphoma: For patients whose cancer has come back or worsened after at least two prior treatments.
- Follicular lymphoma: For previously treated patients, used in combination with rituximab (an antibody therapy).
- Marginal zone lymphoma: Also for previously treated patients, combined with rituximab.
Revlimid is explicitly not recommended for chronic lymphocytic leukemia (CLL) outside of clinical trials.
How Revlimid Works
Revlimid is classified as an immunomodulatory drug, meaning it changes how the immune system behaves. It is chemically related to thalidomide but was designed to be more effective with a different side effect profile. Its anti-cancer activity comes from several overlapping mechanisms working at once.
First, it activates the body’s own T cells and natural killer (NK) cells, two types of immune cells that identify and destroy cancer. At the same time, it dials down regulatory T cells, which normally act as brakes on the immune response. This combination essentially unleashes the immune system against tumor cells. Second, Revlimid disrupts the connection between cancer cells and the surrounding bone marrow tissue that feeds and protects them. Cancer cells in the bone marrow rely heavily on this structural support, and severing it makes them more vulnerable. Third, the drug triggers a self-destruct process in cancer cells (called apoptosis), partly by activating internal enzymes that break down the cell from within. When paired with dexamethasone, these effects are amplified, which is why the two drugs are frequently prescribed together for multiple myeloma.
Multiple Myeloma: The Most Common Use
Multiple myeloma is a cancer of plasma cells in the bone marrow. It is by far the most common reason Revlimid is prescribed. The drug plays a role at two distinct stages of treatment. In active disease, it is paired with dexamethasone (and sometimes a third drug) to reduce the number of cancer cells. After a patient undergoes a stem cell transplant, Revlimid is then used as maintenance therapy, taken continuously at a lower dose to help prevent or delay the cancer from returning.
Maintenance therapy with Revlimid after transplant has become standard practice because it extends the period of remission. However, long-term use does carry some risk. A 2014 analysis of over 3,200 patients across seven clinical trials found a slightly higher rate of second, unrelated cancers when Revlimid was combined with a chemotherapy drug called melphalan. This is something doctors weigh against the clear benefit of delayed relapse when planning a maintenance strategy.
Treating MDS With a Specific Genetic Marker
Myelodysplastic syndromes are a group of conditions where the bone marrow doesn’t produce enough healthy blood cells. Revlimid is approved for a narrow subset of MDS patients: those who have low- or intermediate-1-risk disease, need regular red blood cell transfusions (defined as at least two units within eight weeks), and carry a specific chromosomal deletion known as del(5q). This genetic change occurs on chromosome 5 and is the feature that makes these patients particularly responsive to Revlimid.
For patients who fit this profile, Revlimid can reduce or eliminate the need for transfusions. The tradeoff is significant blood count drops during treatment. In clinical studies, about 59% of MDS patients developed neutropenia (dangerously low white blood cells) and 80% experienced severe enough blood count problems to require a dose reduction or temporary pause in treatment. Blood counts are typically monitored weekly for the first two months and at least monthly after that.
Common Side Effects
Side effects vary somewhat by condition, but three stand out across all approved uses: low white blood cell counts (neutropenia), fatigue, and diarrhea. In multiple myeloma trials, about 42% of patients taking Revlimid with dexamethasone developed neutropenia, compared to just 6% of those on dexamethasone alone. Fatigue affected roughly 44% of patients, and diarrhea occurred in about 39%. In mantle cell lymphoma, the pattern was similar: neutropenia in 49%, fatigue in 34%, and diarrhea in 31%.
These numbers mean that most patients will experience at least one of these side effects during treatment. Dose adjustments are common and expected. Your treatment team will monitor blood work regularly and may temporarily stop or lower your dose if counts drop too far.
Serious Safety Warnings
Revlimid carries three boxed warnings, the most serious category of safety alert the FDA issues.
The first is the risk of severe birth defects. Revlimid is related to thalidomide, which caused devastating birth defects in the 1950s and 1960s. Taking Revlimid during pregnancy can cause birth defects or fetal death. Because of this risk, the drug is only available through a restricted program called REMS. Women who can become pregnant must use two forms of birth control simultaneously, starting four weeks before treatment and continuing for four weeks after stopping. Pregnancy tests are required weekly for the first month and then every two to four weeks throughout treatment. Men taking Revlimid must use condoms during sexual contact with anyone who is or could become pregnant, and they cannot donate sperm.
The second warning involves blood clots. Patients with multiple myeloma treated with Revlimid in combination therapy have a significantly higher risk of deep vein thrombosis (blood clots in the legs) and pulmonary embolism (clots in the lungs). Symptoms to watch for include leg swelling, shortness of breath, and chest pain. Preventive blood thinners are sometimes prescribed alongside Revlimid depending on individual risk.
The third warning is severe drops in blood cell counts, particularly white blood cells and platelets. This is most pronounced in MDS patients, where grade 3 or 4 blood count toxicity was seen in 80% of study participants.
How It Is Taken
Revlimid comes as a capsule in six strengths: 2.5 mg, 5 mg, 10 mg, 15 mg, 20 mg, and 25 mg. It is taken once daily, swallowed whole with water. Capsules should not be opened, broken, or chewed. It can be taken with or without food, ideally at the same time each day. The specific dose depends on which condition is being treated and how well a patient tolerates the medication.
Because of the REMS program, Revlimid cannot be picked up at a regular pharmacy. Patients must enroll in the program, sign an agreement form with their prescriber, and fill prescriptions through certified pharmacies. Blood donation is not allowed while taking the drug or for four weeks after stopping.
Cost and Access
Revlimid is a high-cost specialty medication. Several financial assistance programs exist for patients who have trouble covering out-of-pocket costs. The manufacturer provides patient support specialists who can help insured patients find alternative funding. Organizations like the HealthWell Foundation and the Patient Access Network Foundation offer copay assistance grants for eligible patients with insurance. Medicare beneficiaries may qualify for low-income subsidies to help cover the drug’s cost under Part D.