pash413 ★ India, 2012-03-28 18:04 (4200 d 06:04 ago) Posting: # 8343 Views: 5,584 |
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Dear All We are planing to conduct biostudy for EU submission and we need some clarity regarding below mentioned points:
Should we have to analyze (bioanalysis) plasma samples of that dropped/withdraw subject(s)? We are confusing with the statement of current guidance "if available...." |
Helmut ★★★ ![]() ![]() Vienna, Austria, 2012-03-28 18:27 (4200 d 05:40 ago) @ pash413 Posting: # 8344 Views: 4,893 |
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Dear Pash! ❝ 1. As per current EU guideline statistical evaluation of Tmax is not required, if our drug is not rapid release formulation. In old guidance it was mentioned as “if appropriate to the evaluation the analysis technique for Tmax should be non-parametric and should be applied to un-transformed data”. You are mixing things up. Both quotes come from IR guidelines. A statistical evaluation of tmax is not required. However, if rapid release is claimed to be clinically relevant and of importance for onset of action or is related to adverse events, there should be no apparent difference in median tmax and its variability between test and reference product.
![]() ❝ Is it required to performed statistical evaluation of Tmax in studies conducted after implementation of new guideline? No. But don’t ask me how to assess the variability if required. F**ing boxplots again (like in the assessment of outliers in replicate studies)? ❝ Our formulation is not rapid release formulation. So what is it exactly? CR, DR, multiphasic, pulsatile,…? Tmax is not mentioned in the MR guidance from 1999. Not even for MR formulations where rapid onset is of importance tmax is required (see here). ❝ Should we have to analyze (bioanalysis) plasma samples of that dropped/withdraw subject(s)? Yes. — 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 |
pash413 ★ India, 2012-03-28 19:04 (4200 d 05:03 ago) @ Helmut Posting: # 8345 Views: 4,833 |
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Dear HS Thanks for your quick reply
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Helmut ★★★ ![]() ![]() Vienna, Austria, 2012-03-28 19:49 (4200 d 04:19 ago) @ pash413 Posting: # 8346 Views: 4,986 |
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Dear Pash! ❝ 1. Our formulation is IR formulation, but the reported Tmax is around 6-10 hours. So I assume that rapid onset most likely is neither a clinical claim nor related to AEs. Assessment of tmax is not required. ❝ 2. […] Will it be useful to establish any correlation between adverse events with the plasma concentration data and may be used to rule out formulation performance as the reason of adverse events? Exactly (see here). Sometimes even a subpopulation of ultraslow metabolisers turn up. See the end of this post. ❝ then what about it's applicability for subject who dropout due to personal reason? You never know. Sometimes volunteers don’t report AEs and withdraw consent “for personal reasons” fearing that otherwise they won’t be included in future studies. We once performed a multiple dose PK interaction study on orphenadrine where a volunteer dropped out after the 4th dose. No AEs reported, but trough values were rising significantly faster than in any other subject of the study and would have lead to 10fold higher concentrations in steady state… ❝ […] as USFDA does not require analysis of such dropout subjects. Here I fully agree with EMA’s position. — 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 |