FOSFESTROL

Background and Date of Approval

Fosfestrol is a hormonal chemotherapy medication containing fosfestrol as its active constituent. It is a synthetic estrogen-like medication used to treat certain types of advanced prostate and breast cancer. The prostate is a gland surrounding the urethra just below the bladder and produces seminal fluid that nourishes sperm. Patients with prostate cancer may experience difficulty urinating, blood in urine and semen, bone pain, weight loss, and erectile dysfunction. Fosfestrol received FDA approval on December 20, 1957, for treatment of advanced prostate cancer. It may be used in combination with other medications or treatments to further improve outcomes for patients. Fosfestrol can be a useful treatment option for men unable to undergo surgery or radiation therapy, or who have not responded well to other forms of chemotherapy.

Uses

Fosfestrol is used for the treatment of advanced prostate cancer and advanced breast cancer.

How is it administered?

Fosfestrol is an oral medication usually taken once a day, at approximately the same time each day, with or without food. It should be taken as prescribed by a doctor or other healthcare provider. These capsules should be swallowed whole with a glass of water. They should not be crushed, chewed, or opened, as this can affect the way the medication is absorbed and decrease its effectiveness. You should not take a double dose to make up for the second dose.

Side Effects

Fosfestrol, like all medications, can cause side effects. Some of the more serious side effects include blood clots, stroke, heart attack, and liver damage. These side effects are rare, but they can be severe and potentially life-threatening. Other common side effects may include nausea, vomiting, diarrhea, loss of appetite, weight loss, hot flashes, impotence, and breast enlargement in men. It can also cause changes in blood chemistry, such as elevated levels of calcium and phosphorus, which can lead to bone pain, kidney damage, and other complications.

Warnings

Fosfestrol can increase the risk of blood clots, which can lead to serious health problems such as stroke, heart attack, or pulmonary embolism (blood clot in the lung). This medication can affect blood sugar levels and can worsen diabetes in some patients which in turn results in an increased risk of infection and poor wound healing. It can cause changes in vision, including blurred vision or loss of vision. In rare cases, this medication results in osteoporosis (bone loss) and increases the risk of fractures.

Precautions

Fosfestrol can increase the risk of blood clots, which can lead to serious health problems such as stroke, heart attack, or pulmonary embolism (blood clot in the lung). This medication can affect blood sugar levels and can worsen diabetes in some patients which in turn results in an increased risk of infection and poor wound healing. It can cause changes in vision, including blurred vision or loss of vision. In rare cases, this medication results in osteoporosis (bone loss) and increases the risk of fractures.

Word of Advice

Report any side effects or concerns to your healthcare provider promptly whilst receiving fosfestrol treatment. To reduce your risk of falls and fractures, use assistive devices as needed, wear appropriate footwear, and engage in regular physical activity as recommended by your doctor. If you are pregnant, planning to become pregnant, or breastfeeding, discuss the risks and benefits of fosfestrol with your healthcare provider. Women of reproductive age should use effective contraception during treatment and for at least two weeks after the final dose. Lifestyle modifications including smoking cessation, maintenance of a healthy weight, and a balanced diet support overall health and may reduce the risk of complications associated with cancer.

References

KD Tripathi, Essentials of Medical Pharmacology, Anticancer drugs, 7th edition, 2013, 872. Chabner, B. A., & Longo, Cancer Chemotherapy and Biotherapy: Principles and Practice, 6 edition, 2019, 700-701. Kaye, S. B., Kerr, D. J., & Tait, D, Textbook of Medical Oncology, 4th edition, 2015, 305-306. DeVita, V. T., Lawrence, T. S., & Rosenberg: Principles & Practice of Oncology, 10th edition, 2015, 922-923. Mauro Orlando et al; Low-dose continuous oral fosfestrol is highly active in 'hormone-refractory' prostate cancer; Annals of Oncology; [Published on March 2000]; [Accessed on 22 April 2023], https://www.researchgate.net/publication/12554273_Low-dose_continuous_oral_fosfestrol_is_highly_active_in_'hormone-refractory'_prostate_cancer

Frequently Asked Questions

Can fosfestrol be used in children?

No, fosfestrol has not been studied in pediatric populations and is not approved for use in children.

Can fosfestrol cause weight gain?

Weight gain is not a commonly reported side effect of fosfestrol. However, if you experience unexplained weight gain or swelling, you should consult your healthcare provider .

Can fosfestrol cause changes in hair growth?

Hair loss or changes in hair growth are not commonly reported side effects of fosfestrol. However, if you experience hair loss or changes in hair growth, you should discuss this with your healthcare provider.

Can fosfestrol affect fertility?

Fosfestrol may cause temporary or permanent infertility in some patients, particularly in men receiving high doses. If you are concerned about fertility, you should discuss this with your healthcare provider.

Can fosfestrol be used in patients with kidney disease?

Fosfestrol should be used with caution in patients with kidney disease as it is eliminated from the body primarily through the kidneys. Your healthcare provider may need to adjust your fosfestrol dose or monitor your kidney function more closely if you have pre-existing kidney disease.

Can fosfestrol be used in patients with heart disease?

Fosfestrol should be used with caution in patients with heart disease as it may increase the risk of blood clots or cardiovascular events. Your healthcare provider may need to monitor your heart function more closely if you have pre-existing heart disease.

Can I take Fosfestrol if I am diabetic?

Fosfestrol should be used with caution in diabetic patients. It can increase the risk of high blood sugar levels. Therefore, regular monitoring of blood sugar levels in diabetic patients.

Available Brands 1

Written By: Muskan Patel, M.Pharm

Reviewed By: Dr. Vishwa Patel, MBBS