Which antineoplastic agent does NOT require a test dose?

Dactinomycin, the correct answer, is an antineoplastic agent that does not require a test dose prior to administration. The rationale behind this stems from the pharmacological properties and safety profile of dactinomycin.

For many chemotherapeutic agents, especially those that have a higher risk of causing allergic reactions or significant toxicity, a test dose is given to ascertain the patient's tolerance. However, dactinomycin is generally well-tolerated, and adverse reactions are not frequent enough to necessitate a test dose. Instead, monitoring the patient for immediate reactions during the first full dose is sufficient.

Other agents listed, such as daunorubicin, carmustine, and mitomycin, typically involve a test dose due to their potential for severe allergic reactions or toxicity. This precaution helps healthcare providers gauge the patient’s response and safety before administering a full therapeutic dose.