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RegisterEMA: GL on bioanalytical method validation Rev.1 [Regulatives / Guidelines]
❝ 2. Section 6 ‘Incurred samples reanalysis’
❝ • old
❝ The concentration obtained for the initial analysis and the concentration obtained by reanalysis should be within 20% of their mean […].
❝ • new
❝ The concentration obtained for the initial analysis and the concentration obtained by reanalysis should be within 20% of their mean […]. The following equation should be used for the calculations:
❝ (repeat value – initial value)
❝ %difference = ────────────────────────────── ×100
❝ mean value
The text actually changed from
The concentration obtained for the initial analysis and the concentration obtained by reanalysis should be within 20% of their mean for at least 67% of the repeats
to
The percent difference between the initial concentration and the concentration measured during the repeat analysis should not be greater than 20% of their mean for at least 67 % of the repeats
which may be a bit clearer. The initial wording could be interpreted as allowing a 40 % deviation (20 % below the mean, 20 % above it).
❝ 3. Section 7.1.1.11. ‘Stability of the samples’
❝ • old
❝ In addition, long-term freezer stability should be studied at each temperature at which study samples will be stored. A bracketing approach may be considered.
❝ • new
❝ In addition, long-term freezer stability should be studied at each temperature at which study samples will be stored. A bracketing approach may be considered.
❝
❝ But why #3? If one has already shown stability at –80 ℃ and –20 ℃ – intending to store samples at any temperature in between – that’s an unscientific formalism, IMHO (yes; I’m aware about some Crystal City Conference discussions).
This is only for large molecules (section 7 of the guideline), not small molecules. The deletion removes the contradiction between 7.1.1.11 (which allowed bracketing) and 4.1.9 (which allows bracketing for small molecules, but excludes it for large molecules). If I remember correctly the discussions in Brussels in 2010, this was due to possible problems with the structural conformation of proteins, right ?
Regards
Ohlbe
Complete thread:
- EMA: GL on bioanalytical method validation Rev.1 Helmut 2014-09-19 17:09
![[Mix]](https://static.bebac.at/img/mix.png "open in Mix view")
- EMA: Guideline on bioanalytical method validation Rev.1 ElMaestro 2014-09-19 17:39
- EMA: NSA-approach Helmut 2014-09-19 18:02
- EMA: NSA-approach ElMaestro 2014-09-19 19:28
- EMA: NSA-approach nobody 2014-09-19 19:41
- EMA: NSA-approach ElMaestro 2014-09-20 21:41
- EMA: NSA-approach nobody 2014-09-21 16:59
- EMA: NSA-approach ElMaestro 2014-09-20 21:41
- EMA: NSA-approach nobody 2014-09-19 19:41
- EMA: NSA-approach ElMaestro 2014-09-19 19:28
- EMA: NSA-approach Helmut 2014-09-19 18:02
- EMA: GL on bioanalytical method validation Rev.1Ohlbe 2014-09-19 19:20
- THX! Helmut 2014-09-22 16:34
- EMA: GL on bioanalytical method validation Rev.1 Roberto 2014-09-23 17:52
- EMA: Guideline on bioanalytical method validation Rev.1 ElMaestro 2014-09-19 17:39
Ing. Helmut Schütz