Lomustine (INN; abbreviated as CCNU; original brand name CeeNU, now marketed as Gleostine) is an alkylating nitrosourea compound used in chemotherapy.

[10] While current data is only based on animal studies, there is reason to believe that lomustine use during pregnancy can cause harm to a fetus, potentially leading to miscarriages or birth defects.

Patients are advised to use birth control with partners while taking lomustine due to the potential for fetal harm.

[8] While there are no clinical studies on lomustine use in the 65+ age group, clinicians are recommended to exercise caution in prescribing this drug to geriatric patients.

Lomustine causes high levels of organ toxicity, which must be taken into account when determining dosing for elderly patients.

[5] Clinical trials have demonstrated the drug's success in treating progressive lymphomas, mast cell tumors, and brain cancers.

This chemotherapy has been observed to have a variety of side effects in animals, paralleling those in humans, including but not limited to bone marrow immunosuppression, gastrointestinal issues, and hepatotoxicity.

Due to the cytotoxic nature of lomustine, the drug must be dosed, administered, and disposed of with special precautions including wearing gloves to prevent dermal exposure.

[8] Long term use of lomustine is linked to secondary malignancies including acute leukemia and myelodysplasia, due to the drug's DNA alkylating properties.

Patients' complete blood counts should be consistently monitored during treatment in order to mitigate the myelosupressive risks of the drug and prevent fatal complications such as infections and internal bleeding.

Overdoses may lead to heightened myelosupression, abdominal pain, diarrhea, vomiting, anorexia, extreme fatigue, dizziness, liver failure, and shortness of breath.

[8] Non-fatal overdose management includes hospitalization and antibiotic treatment to address myelosuppressive effects of lomustine.

[13] Lomustine is a cell cycle non-specific, highly lipophilic alkylating agent which produces chloroethyl carbenium ions and carbamylating intermediates in vivo.

Unlike other anticancer agents like mitomycin C, streptonigrin, bleomycin, and the anthracyclines, lomustine does not require bioactivation to react with cellular targets.

[20] Lomustine is a chloroethlyating compound and it causes alkylation and cross-linking of RNA and DNA at the O6 position of guanine-containing bases.

Lomustine is administered orally in six-to-eight-week intervals and with nadirs at five weeks after administration due to its delayed myelosuppressive properties.

Lomustine, alone or in combination with other chemotherapeutic drugs, was the standard of care following surgery and/or radiation up until the early twenty-first century.

[25] NextSource recognized the medical importance of lomustine, so they acquired the manufacturing rights from Bristol-Myers-Squibb in partnership with Corden Pharma.

This was the first time in history that a company with a drug eligible for coverage under the Medicare Part D benefit made the decision to leave the program.

In July 2021, the list price for the highest dose of lomustine was 1900% higher than it was in 2013, when it was being manufactured and sold by Bristol-Myers Squibb.

[26] In December 2021, the Glioblastom Foundation announced a new partnership with Continuity Pharma to manufacture a generic form of lomustine.

The agreement allowed the drug to be manufactured in the United States, which made it more accessible to patients and lowered the cost of brain cancer treatment by approximately 90%.