An optical imaging agent shown to improve diagnostic accuracy, pafolacianine (Cytalux) was approved on November 29, 2021, for use in adult patients with known or suspected ovarian cancer as adjunct therapy in conjunction with planned intraoperative identification of malignant lesions. Pafolacianine is used in combination with a near-infrared (NIR) fluorescence imaging system that requires specialized training provided by the device manufacturer.

Category/Class

Fluorescent diagnostic optical imaging agent

Mechanism of Action

Pafolacianine attaches to folate receptor (FR)-expressing cancer cells, is internalized into the cell via receptor-mediated endocytosis, and then concentrates in the FR-positive cancer tissue. The concentrated areas emit fluorescence that is detected with NIR imaging for identification and removal during surgery.

Indication

Adult patients with pathologically confirmed or clinically suspected ovarian cancer who are undergoing surgical intervention for primary cytoreduction, interval debulking, or management of recurrent disease

Dosing

Single IV infusion of 0.025 mg/kg diluted in 250 ml of 5% dextrose injection

Administration

Infuse over 60 minutes using a dedicated infusion line one to nine hours prior to surgery. Protect the infusion bag with a light-blocking cover during administration.

Adverse Reactions

Among the 294 patients in the three open-label trials, adverse reactions occurred during and after administration and included nausea (15%), vomiting (5.8%), abdominal pain (2.7%), flushing (1.7%), dyspepsia (1%), chest discomfort (1%), and pruritus (1%). Additionally, 2.4% of patients experienced infusion reactions during administration, typically starting within 15 minutes of initiation.

Drug-Drug Interactions

Folate, folic acid, or folate-containing supplements taken 48 hours before administration may reduce binding to ovarian cancer cells’ FRs.

Nursing Considerations

Pafolacianine may cause fetal harm when administered to pregnant patients. Obtain and confirm a negative pregnancy test in females of reproductive potential prior to administration. Review patients’ medication list for drug-drug interactions such as folate.

Pretreat with antihistamines or antinausea medication if patients require infusion reaction prophylaxis, and monitor patients throughout administration. If a reaction occurs, pause the infusion and administer antihistamines or antinausea medications as ordered. Resume the infusion once symptoms resolve, provided it is completed within three hours of its initial start time.

Visually inspect the admixture for signs of aggregation prior to infusion. Dextrose 5% injection must be used as the diluent; other diluents can cause aggregation that may provoke infusion reactions.

Patient Education

Advise females of reproductive potential of the possible risk to a fetus and to use contraception prior to administration. Discuss the planned surgical procedure and expected outcomes on fertility. Discuss the possibility of false-negative and false-positive findings: nonfluorescing tissue in the surgical field cannot unequivocally exclude the presence of ovarian cancer, whereas noncancerous tissue or general inflammation may demonstrate fluorescence. Advise patients to stop taking folate, folic acid, or folate-containing supplements 48 hours before administration. Inform them about the infusion reaction symptoms to report immediately.

Gero-Oncology Considerations

In the agent’s clinical trials, 40% of patients were aged 65 or older and 11% were aged 75 and older. No overall differences in safety, effectiveness or pharmacokinetics were observed between older patients and younger patients.

Safe Handling

Carcinogenicity and reproductive and developmental toxicity studies have not been performed. Pafolacianine may cause fetal harm.