long acting Injection [Design Issues]

posted by pankajsojitra – India, 2020-04-19 11:15 (163 d 13:09 ago) – Posting: # 21336
Views: 2,275


Hope all are well and safe.

Just need your help to understand one of aspect of study design as mentioned below.

Usually, 5 half-lives are considered for steady state in pharmacokinetic BE study.

But if it is mentioned in monograph that half-life is 17 days following single dose and 46 days after multiple dose, then which half-life we should consider while designing multiple dose study? In the same monograph, it is also stated that steady state is achieved after 4th dose on injection.

If we consider 17 days half life, then steady state achievement after 4th dose seems ok and we can proceed with 4, 5, 6 dose PK sampling. But if we consider 46 days (as it is with multiple dose and proposed study would also the same), then we need 9 monthly doses to build 5 half lives and 9, 10, 11 dose PK sampling.

Please guide in this regard.


Edit: Category and subject line changed; see also this post #1 &#2[Helmut]

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