Bhupesh ☆ India, 2009-10-12 16:14 (5282 d 00:00 ago) Posting: # 4339 Views: 7,168 |
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Dear All Regards Few days back, we did a parallel bioequivalance study for a molecule with long half life (terminal elimination half life between 120 hr - 156 hr) and have sampling points up to 720 hrs post dose. Due to longer study period, there were some missing ambulatory samples (In one volunteer missed 3 samples between 72 - 144 hr) and in others missing some samples after 144 hr. Tmax of the molecule was said to be in between 6 - 24 hr. Can anyone please suggest a reliable estimation of AUC0-t considering the missing samples. Thanks and Regards Bhupesh Edit: Category changed. [Helmut] |
Jaime_R ★★ Barcelona, 2009-10-12 16:51 (5281 d 23:23 ago) @ Bhupesh Posting: # 4340 Views: 5,812 |
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Dear Bhupesh! Why didn't you use a truncated AUC72 approach? The rationale for truncated AUC is:
You have some options to deal with the problem (caution: don't evaluate for BE right now. Make a decision and amend the protocol accordingly):
— Regards, Jaime |
yjlee168 ★★★ Kaohsiung, Taiwan, 2009-10-13 00:53 (5281 d 15:21 ago) @ Jaime_R Posting: # 4343 Views: 5,765 |
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Dear Jaime_R, ❝ Why didn't you use a truncated AUC72 approach? The rationale [...] Since the study has been done, was it too late to switch to truncated AUC method? unless the protocol did not state the exact method... but it seems not possible. ❝ You have some options to deal with the problem (caution: don't evaluate [...] These are very nice suggestions! These should be carefully considered when developing a BE study protocol. I've learned. — All the best, -- Yung-jin Lee bear v2.9.1:- created by Hsin-ya Lee & Yung-jin Lee Kaohsiung, Taiwan https://www.pkpd168.com/bear Download link (updated) -> here |
Jaime_R ★★ Barcelona, 2009-10-13 20:24 (5280 d 19:50 ago) @ yjlee168 Posting: # 4349 Views: 5,648 |
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Dear Yung-jin! ❝ ❝ Why didn't you use a truncated AUC72 approach? ❝ Since the study has been done, was it too late to switch to truncated AUC ❝ method? Oh yes, sure. I should have added a to my rhetorical question... ❝ ❝ You have some options [...] ❝ These are very nice suggestions [...] should be carefully considered ❝ when developing a BE study protocol. Maybe. But I would put all efforts not running into such a situation, i.e. avoid sampling for one month. — Regards, Jaime |
Helmut ★★★ Vienna, Austria, 2009-10-12 17:18 (5281 d 22:56 ago) @ Bhupesh Posting: # 4341 Views: 5,778 |
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Dear Bhupesh agreeing with Jaime's post one more caveat: depending on the software you use, it may be dangerous to keep these values only as 'Missing'. For instance WinNonlin always interpolates linear - leading to a positive bias of the calculated AUC. See this post and this one as well. There's a tricky (and undocumented) workaround to get a correct estimate (essentially adding two partial areas), but this is nothing for beginners. — Dif-tor heh smusma 🖖🏼 Довге життя Україна! Helmut Schütz The quality of responses received is directly proportional to the quality of the question asked. 🚮 Science Quotes |