Final answer:
While the exact grades of allowable toxicity for continuing a dose of study drug are not mentioned, grades 1 and 2 on the CTCAE scale are typically considered mild to moderate and may permit continued dosing. Toxicokinetics plays a key role in determining these levels by assessing the safety and efficacy of a drug, especially in vulnerable populations.
Step-by-step explanation:
The two grades of allowable toxicity which would permit a patient to continue receiving a dose of study drug are not specifically mentioned in the provided text. Generally, in clinical trials, these grades are based on a scale such as the Common Terminology Criteria for Adverse Events (CTCAE), which is used to classify side effects of drugs within oncology trials. Allowable toxicity levels are typically those that are considered mild to moderate (for example, Grade 1 and Grade 2 toxicity) and do not significantly impact patient quality of life or require significant medical intervention.
Toxicokinetics is essential in the evaluation of toxicity as it helps to determine the dose/exposure relationship and the margin of safety. It involves measuring the plasma concentrations of the drug and its metabolites, and it is crucial for defining the human equivalent dose and the maximum recommended starting dose in first-in-human clinical trials. The goal is to establish the optimum dosage with minimum side effects while maintaining efficacy, which is especially critical for vulnerable populations such as pediatric, elderly, or patients with impaired renal or hepatic functions.