geocappy, no it is not.
You must show that the delays are due to OTHERS (FDA,FCC, etc) and that you never made any use of the patent in the period on which base you request the extension in a way that would be otherwise protected by the patent (marketing, import/export, sell, etc).
Limited resources would not be caused by a MANDATORY procedure such as a clinical trial. It would be caused by the company not correctly planning the financing of such trial which is clearly a cause of the company, hence no extension.
AIMO