More than 7,500 women are diagnosed with ovarian cancer each year in the UK. It is estimated that by 2040 this number will increase to 9,400.
For more than 30 years, platinum-based chemotherapy has been the standard of care for ovarian cancer. But while patients usually respond well to this treatment initially, in about 70% of patients the cancer recurs and becomes resistant to the treatment.
Once resistance emerges, patient outcomes are poor – the five-year survival rate is about 50%.
The approval of Alahere will help hundreds of women living in England who have treatment-resistant cancer, delaying cancer progression and prolonging life.
Elahere is an antibody drug conjugate (ADC). ADCs are a relatively new class of cancer treatments that have been developed specifically to deliver highly potent chemotherapy to cancer cells. This progress is a necessary step away from typical chemotherapy, which can damage both cancer cells and healthy cells and tissues when administered.
ADCs use antibodies, which are a type of immune protein. Antibodies are able to recognize cancer cells because of a protein found on their surface that is present in very high levels. This same protein is not normally found on healthy cells.
A chemotherapy agent is hidden within these antibodies so that the antibody does not cause any harm to healthy cells during circulation and attacks only the cancer cells. This chemotherapy agent is even more powerful than the chemotherapy agents used in standard treatment.
The antibody and the drug are bound to each other by a chemical bridge known as a linker that releases the drug from the antibody only after it has entered the cancer cells. The antibody attaches itself to a cancer cell, hijacking a normal biological process called endocytosis that pulls the antibody into the cell.
Once the ADC is inside the cell, the linker will be cut by the enzymes inside it. This allows the antibodies to release the chemotherapy, destroying the cancer cell.
Elahere specifically targets the protein folate receptor-alpha (FR-alpha). FR-alpha protein is found at high levels on many ovarian cancer tumors and including those that have undergone metastasis (cancer that has spread from the site of the primary tumor).
About 35% of patients with platinum-resistant ovarian cancer are eligible for treatment with Elahere, which is a significant proportion. Tumor biopsy will need to be tested for FR-alpha levels to confirm patient eligibility.
In clinical trials, patients with high FR-alpha were selected for treatment with Elahere when they became resistant to platinum-based chemotherapy treatments. Resistance was classified as people who had received one to three rounds of first-line chemo, but their cancer still grew within six months of the last round of treatment. These patients had limited treatment options and high mortality rates.
Clinical research showed that Elahere was able to delay the progression of cancer. Patients treated with Elahere lived longer on average than patients treated with other chemotherapy.
Patients who were treated with Elahere lived about 17 months after treatment, while those who received other types of chemotherapy lived only about 13 months.
A new treatment option for women with platinum-resistant ovarian cancer
Elahere will be offered to patients with specific types of ovarian cancer – called high-grade serous epithelial ovarian, fallopian tube or primary peritoneal cancer. They may also develop resistance to conventional chemotherapy after receiving one to three rounds of this class of therapy.
Ovarian cancer is a devastating disease. It is very difficult to diagnose until it reaches advanced metastatic stage and the disease has low survival outcomes.
The results of Elahere treatment are comparatively very effective, and it appears to be associated with fewer side effects than chemotherapy.
The approval of Elahere is a successful treatment. Its use increases the life expectancy and quality of life of the patients treated with it.
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