Less specifics on Clinical Trial Durations in Guidelines
There are less specifics on duration that I could find in Guidelines for clinical trials, but the information there does support Dr. Seymour's statement "it is possible to complete human trials in the space of a few short months".
All the testing - non-clinical and clinical builds on itself. From ICH E8 - General Considerations for Clinical Trials:
The cardinal logic behind serially conducted studies of a medicinal product is that the results of prior studies should influence the plan of later studies.
So for Phase 1 (as much as I can determine from the guidelines) - Testing duration to clinical follow-up would be expected to be similar to the non-GLP and GLP Tox testing (~2 weeks). There may be multiple dose regimens, so they may not be able to do all in parallel increasing the time somewhat. It also takes time to enroll all patients (although the number of patients is small). In addition, some assessments such as blood/fluids testing may take a little more time beyond the duration of the clinical followup. And there is also the collecting, auditing, statistical and practical analysis of the data and documentation in reports. BUT THIS IS MUCH FASTER THAN ALMOST ALL OTHER DRUG DEVELOPMENT PROGRAMS - EVEN WITHOUT ACCELERATED REGULATORY OPTIONS.
For Phase IIa,b, III - Testing would be expected to be up to the longer duration of either the previous safety assessments (non-clin and Phase I clin of ~2 weeks) or the duration of this illness (Flu in this case). For Phase IIa, there may also be a period between Flu administration and FluCide administration. Again, this is also faster than other drug programs.
References:
From ICH E6(R1) - Guideline for Good Clinical Practice (GCP). [Also looked at E8,E4]
5.12.1 When planning trials, the sponsor should ensure that sufficient safety and efficacy data from nonclinical studies and/or clinical trials are available to support human exposure by the route, at the dosages, for the duration, and in the trial population to be studied.
The following is an excerpt from ICH M3(R2) under the section "Single-Dose Trials at Subtherapeutic Doses or Into the Anticipated Therapeutic Range (7.2)", footnote c. to "Table 3 Recommended Nonclinical Studies to Support Exploratory Clinical Trials":
Generally, extended single dose toxicity studies should be designed to evaluate hematology, clinical chemistry, necropsy, and histopathology data (control and high dose only if no treatment-related pathology is seen at the high dose) after a single administration, with further evaluations conducted 2 weeks later to assess delayed toxicity and/or recovery. The usual design for rodents consists of 10 animals/sex/group to be assessed on the day following dosing, and 5 animals/sex at the dose level(s) selected to be assessed on day 14 post-dose. The usual design for nonrodents consists of 3/sex/group for all groups on day 2 and 2/sex for the dose level(s) assessed on day 14.