Advances In Folate Receptor-Positive Ovarian Cancer
- Folate receptor-positive ovarian cancer cells have receptors that allow folate in, fueling their growth.
- Doctors can use immunohistochemistry (IHC) tests to measure folate receptor levels in cancer cells, and patients may qualify for free testing.
- Elahere is an FDA-approved drug that specifically targets cancer cells with folate receptors, minimizing damage to healthy cells.
- Clinical trials are exploring other drugs, like farletuzumab and STRO-002, which target folate receptors in ovarian cancer cells.
Imagine tiny doors on cancer cells, called “folate receptors,” that allow a vitamin needed for growth called folate into both healthy and cancerous cells.
Up to 80% of ovarian cancers have extra “doors” (folate receptors) that fuel their growth. This type of disease, called folate receptor-positive ovarian cancer is usually late stage, aggressive and serious.
Read MoreAnd they also have an FDA-approved medicine, Elahere, that specifically treats it by directly targeting the cancer cells while leaving healthy cells unharmed.
Related: Remembering Coretta Scott King and the Impact Ovarian Cancer Left on Her Children
What tests will tell me if my cancer is folate receptor positive?
If your ovarian cancer comes back, doctors may check for the level of folate receptors on the cancer cells by taking a small tissue sample (biopsy) and sending it to the lab for an IHC to measure the amount of folate receptor alpha (FRα) protein found on the surface of your cancer cells.
Dr. Crispens explains what the test is looking for: “This isn’t sequencing, this isn’t next generation sequencing of the tumor. It’s a very specific test… where they can basically take an antibody, put it on the slide that has the cancer and see what percentage of the cells are folate receptor alpha positive and that’s how they determine eligibility.
“It needs to be 70% or more. If it’s really not highly over expressing, we know that the medicine’s not likely to work” she adds.
Most doctors don’t routinely order this test. But you should bring it up with your doctor to see if it makes sense for you to have it. Knowing more about your cancer sooner than later can lead to a longer , healthier life.
If you meet the following criteria, your doctor can order the test and you can have it free of charge:
- Have ovarian, fallopian tube, or peritoneal cancer
- Live and receive treatment in the US or a US territory
- Haven’t had this test before
- Doctor thinks it’s medically necessary
Two organizations offer this free test in Nashville and elsewhere in the US:
- FR-ASSIST program: Partnered with NeoGenomics and ImmunoGen, your oncologist can request a free IHC test.
- Labcorp FR-ASSIST™ program: Offers a free FOLR1 IHC test for eligible patients.
What is the drug Elahere?
In November 2022, a new treatment called Elahere (mirvetuximab soravtansine) for ovarian cancer that did not respond to 1-3 rounds of chemotherapy.
The drug works by targeting the FRα protein. It attacks the cancerous cells precisely while avoiding doing damage to the surrounding healthy cells. This approach can minimize side effects and offer better results.
“It’s way to target a drug directly to the cancer cells hopefully increasing how effective the drug could be while decreasing the side effects the effects on normal cells,” Dr. Crispens explains.
Elahere currently treats adults with a specific type of ovarian cancer that is FRα-positive, platinum-resistant. This means the cancer has these FRα receptors and hasn’t responded well to standard chemotherapy with a platinum-based drug.
Studies show promising results with Elahere. In one phase 3 trial, over 30% of patients saw their tumors shrink or disappear, with some achieving complete remission, meaning the disease had disappeared completely. The treatment was well-tolerated, with manageable side effects like blurred vision or nausea.
“It has been a big advance for patients with platinum resistant disease to have this medicine that maybe can help have more of a chance for them to respond to and also maybe help prolong their life more than or at least prolong the time to the next recurrence more than other drugs,” Dr. Crispens says.
However, while side effects are generally mild, Elahere does have risks, including:
- Serious eye problems
- Lung inflammation
- Nerve problems (peripheral neuropathy)
“So [you can have] eye problems with inflammation of the eye and problems with vision and you have to have eyedrops to try to prevent that,” Dr. Crispens cautions. “And you have to have periodic exams with an eye doctor to be sure that there aren’t being bad eye complications that could lead to decreased vision or blindness.”
More common side effects:
- Fatigue
- Elevated liver enzymes
- Nausea or abdominal pain
- Reduced red or white blood cell counts
- Diarrhea or constipation
- Lower blood albumin levels
- Reduced blood magnesium levels
Doctors often don’t consider giving Elahere until later in treatment. You can certainly discuss the possibility of using it earlier with your doctor to ensure you explore all options.
Related: Considering The New Ovarian Cancer Treatment Elahere?
Are there other drugs that treat folate receptor-positive cancer?
Researchers are testing new treatments specifically targeting FRα proteins found in some ovarian cancers.
Two drugs are currently in clinical trials which are rigorous studies involving volunteers to assess their safety and effectiveness.These trials help determine if the treatment works and is safe for wider use.
Farletuzumab is a type of protein called an antibody, which is specifically designed to target FRα. When farletuzumab binds to FRα, it works to stop the tumor from growing and spreading.
Currently, farletuzumab is still undergoing clinical testing to assess its safety, effectiveness, and optimal dosing.
Another promising candidate called STRO-002 is an investigational antibody-drug conjugate (ADC) also still in clinical trials.
STRO-002 combines an antibody with a potent toxin. It specifically homes in on FRα-positive cancer cells to deliver the poison and destroy them.
“I would certainly encourage people in that setting to think about clinical trial participation,” Dr. Crispens says. “It’s not for everybody, and I get that, but it’s certainly something to be considered that someone might have access to a drug that might target something about their tumor cell that they might not otherwise have access to.”
Ask your doctor if one of these clinical trials makes sense for you. They can help you identify and apply for the one nearest you.
Related: SurvivorNet Clinical Trial Finder
Questions to ask your doctor
- Is my type of ovarian cancer folate receptor positive?
- Am I eligible for the free folate receptor test?
- Does Elahere seem like a good treatment option for me, given my specific case?
- Are there any potential side effects of Elahere I should be aware of?
- Are there any ongoing clinical trials for other drugs targeting folate receptor positive cancer that I might be eligible for?
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