How Pemetrexed (Alimta®) Is Used to Treat Mesothelioma
According to the National Comprehensive Cancer Network (NCCN), pemetrexed can be delivered as a single agent treatment or in combination with other chemo drugs as a first-line treatment for all types of mesothelioma. For patients who are not candidates for surgery, pemetrexed is often the recommended first-line therapy. As part of a multimodal treatment plan, the American Society of Clinical Oncology (ASCO) notes that pemetrexed can be given either before or after surgery, typically ranging between 4 – 6 treatment cycles. If patients respond favorably to the treatment, they may be allowed to take a break from continued chemotherapy.
Pemetrexed is given to patients through an IV and takes about 10 minutes to complete. The process is performed every three weeks for several cycles, depending on the patient’s individual case. Mesothelioma patients may be able to stay on the drug as part of a maintenance treatment plan if the cancer has remained stable or decreased in size.
Depending on how the body responds to the treatments, a patient’s healthcare team can perform blood tests to determine whether or not the dosage needs to change or if treatment needs to be slowed or stopped altogether. Factors that could alter the treatment schedule include a patient’s overall health, cancer progression, cell type and other prior or future treatments.
Pemetrexed is also supplemented with folic acid, taken orally, and Vitamin B12 injections. This is meant to reduce the risk of a patient developing side effects associated with their chemotherapy regimen.
02. Side Effects
Possible Side Effects of Pemetrexed (Alimta®)
For patients diagnosed with malignant mesothelioma, treatments involving the use of Alimta® have proven effective at killing cancer cells. However, patients may face a number of side effects, which can differ based on how the patient reacts to the treatment and whether or not pemetrexed is given alone or combined with other therapies. By itself, Alimta® is generally well-tolerated, but may cause side effects like fatigue, loss of appetite and nausea. Like many other chemotherapy drugs, there is also a risk of the patient sustaining hair loss or thinning, though it’s low for patients taking Alimta®.
Alimta® has also been less commonly associated with more serious side effects, ranging from painful skin reactions to kidney damage, lung issues and radiation recall. Radiation recall occurs when the body has been treated with radiation prior to receiving Alimta® and generally results in swelling or blistering where the radiation was given.
Patients should also be sure to discuss any other medications and supplements they are taking with their doctors, as it could cause adverse reactions with pemetrexed. According to a 2017 study, researchers noticed that blood problems could develop in patients taking both nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen and pemetrexed with carboplatin, especially for those with renal insufficiencies.
The manufacturers of Alimta® have stated that over-the-counter medications like aspirin or ibuprofen may be given in low doses. Higher doses of these common medications are not recommended because there isn’t enough information about their interactions with pemetrexed.
Studies Associated With Pemetrexed (Alimta®)
In 2003, prior to receiving FDA approval, a phase 3 clinical study showed that patients who received pemetrexed and cisplatin survived about three months longer than those who received cisplatin alone (12.1 months compared to 9.3 months in the control group). Response rates for patients were also much higher in the group receiving the combination therapy, as opposed to the single agent treatment of cisplatin.
In more recent studies, researchers noted that patients with peritoneal mesothelioma also responded to treatments using pemetrexed as either a single agent or combined with a platinum-based drug like cisplatin. According to one study, patients who received pemetrexed alone had a 1-year survival rate of about 42%, while more than 57% of those who received the drug combined with cisplatin survived for one year. On average, peritoneal mesothelioma patients survive six months to one year.
In 2017, another study of 24 malignant peritoneal mesothelioma patients being treated with pemetrexed and cisplatin resulted in two complete responses and nine partial responses, totaling a 45.8% response rate. Patients also saw a median overall survival of 15.8 months using the drug combination.