Final answer:
The FDA can halt the development or use of gene therapy at multiple points: upon an IND application submission, during clinical trials, and after manufacturing and marketing of the approved therapy. The correct answer is D. all of the answers are correct.
Step-by-step explanation:
In the context of gene therapy, the Food and Drug Administration (FDA) can halt the development or use of such therapy at different stages of the product lifecycle. The FDA has the authority to intervene:
On submission of an Investigational New Drug (IND) application, which is a request for authorization from the FDA to administer an investigational drug to humans.
During clinical trials, which are research studies that explore whether a medical strategy, treatment, or device is safe and effective for humans.
After manufacturing and marketing of the approved therapy if new issues with safety, efficacy, or manufacturing arise.
Therefore, the correct answer is D. all of the answers are correct, indicating that the FDA's oversight encompasses the entire progression of gene therapy development and usage.