F2 Calculations HELP PLEASE

[connieg295]

Please forgive a lowly validation person from barging onto your board, but I have found it always helps to go to the experts when you have a guestion.

My boss told me to do an F2 caluculation for some validation testing we recently did. I know about F2 caluculations, but haven't the faintest idea about how to go about doing one. Does any one have a spread sheet set up to do this that they are willing to share. I will be in your debt forever if you can help me.

thanks
connie

[bartjoosen]

http://www.dissolution.com/vbulletin/showthread.php?t=674

[sagarprasanna]

please find here with aatched F2 table
prasanna sagar:cool:

[connieg295]

please find here with aatched F2 table
prasanna sagar:cool:


Thanks for the help. I do approciate it

[ashgupta69]

Dear Prasanna sagar,
I will be greatful to you if you can forward me the excel sheet for the calculation of f1 and f2. I am stuck with the calculation, I did the calcualtion but I am not sure about it, please help me. my mail id is ashokg@sumariagroup.com.
Regards
Ashok

[ashgupta69]

Dear Connieg295,
if you have recd. f2 calcualtion sheet, please forward me on my id ashokg@sumariagroup.com.
thanks
Ashok

[jineshchauhan]

Dear all,
I will be greatful to you if you can forward me the excel sheet for the calculation of f1 and f2. I am stuck with the calculation, I did the calcualtion but I am not sure about it, please help me.

mail id: jineshchauhan@yahoo.com
thanks,

Jinesh

[BHAVESH SHAH]

Dear Jinesh,

Please find the excel file for calculation.

[sujit patel]

Dear Members,

I hereby got an opertunity to share my doubts among all your rich experience and expertise. Myself a newcomer and to say a fresher only. Thuslots ofdoubts are confronted .

In the context of F2 calculation, eventhough the formula refered from FDA guidelines,butall are compact and even I got calculation done by putting the formulain for dissolution profile in excel sheet. But if i am asked to do so by manually, then I can't becoz, I am not aware of the constituting parameters / variables and importance of these. If I could be explained the details of the formula by breaking ,then will enable me to inculcate in my mind set orelse keep on doing mechanically the calculation in excel sheet.

The excel sheet is undoubtedly helpful and userfriendly but being anew comer I should know the manual one which can help me for personal understanding.

Thus waiting for your kind response in this regard.

Thanking you,
SujitPatel

[Ajay.mahajan]

Following article may be useful

Dissolution Profile Comparison Using
Similarity Factor, f2
Vinod P. Shah, Yi Tsong, Pradeep Sathe and Roger L. Williams
Office of Pharmaceutical Science, Center for Drug Evaluation and Research
Food and Drug Administration, Rockville, MD
What is a dissolution profile comparison and what is its impact?
In recent years, FDA has placed more emphasis on a dissolution profile comparison in the area of post-approval changes and biowaivers. Under appropriate test conditions, a dissolution profile can characterize the product more precisely than a single point dissolution test. A dissolution profile comparison between pre-change and post-change products for SUPAC related changes, or with different strengths, helps assure similarity in product performance and signals bioinequivalence.
Among several methods investigated for dissolution profile comparison, f2 is the simplest. Moore and Flanner proposed a model independent mathematical approach to compare the dissolution profile using two factors, f1 and f2 (1).

where Rt and Tt are the cumulative percentage dissolved at each of the selected n time points of the reference and test product respectively. The factor f1 is proportional to the average difference between the two profiles, where as factor f2 is inversely proportional to the average squared difference between the two profiles, with emphasis on the larger difference among all the time-points. The factor f2 measures the closeness between the two profiles. Because of the nature of measurement, f1 was described as difference factor, and f2 as similarity factor (2). In dissolution profile comparisons, especially to assure similarity in product performance, regulatory interest is in knowing how similar the two curves are, and to have a measure which is more sensitive to large differences at any particular time point. For this reason, the f2 comparison has been the focus in Agency guidances.
When the two profiles are identical, f2=100. An average difference of 10% at all measured time points results in a f2 value of 50. FDA has set a public standard of f2 value between 50-100 to indicate similarity between two dissolution profiles.
For a dissolution profile comparison:
· At least 12 units should be used for each profile determination. Mean dissolution values can be used to estimate the similarity factor, f2. To use mean data, the % coefficient of variation at the earlier point should not be more than 20% and at other time points should not be more than 10%.
· For circumstances where wide variability is observed, or a statistical evaluation of f2 metric is desired, a bootstrap approach to calculate a confidence interval can be performed.
· The dissolution measurements of the two products (test and reference, pre- and post- change, two strengths) should be made under the same test conditions. The dissolution time points for both the profiles should be the same, e.g., for immediate release products 15, 30, 45 and 60 minutes, for extended release products 1, 2, 3, 5 and 8 hours.
· Because f2 values are sensitive to the number of dissolution time points, only one measurement should be considered after 85% dissolution of the product.
· For products which are rapidly dissolving, i.e., more than 85% in 15 minutes or less, a profile comparison is not necessary.
· A f2 value of 50 or greater (50-100) ensures sameness or equivalence of the two
curves and, thus, the performance of the
two products.
A general question is how large can the difference between the mean dissolution profiles be before the difference is likely to impact on in vivo performance. From a public health point of view, and as a regulatory consideration, a conservative approach is appropriate. The f2 comparison metric with a value of 50 or greater is a conservative, but a reliable estimate to assure product sameness and product performance.
References:
1. J.W.Moore and H.H.Flanner, Mathematical Comparison of curves with an emphasis on in vitro dissolution profiles. Pharm. Tech. 20(6), : 64-74, 1996.
2. V.P.Shah, Y.Tsong and P.Sathe, In vitro dissolution profile comparison - statistics and analysis of the similarity factor, f2. Pharm. Res. 15: 889-896, 1998.

[bhavin]

Dear connieg295,

please forward me the excel calculation sheet for f1 anf f2 calculation on my following email id.

bhavinp@glenmarkpharma.com

Thanks

[Apharmd Battler]

Wow, lots of responses in this thread. I'd like a copy of the f1 & f2 spreadsheets for myself. I'm curious as if you can customize the number of time points in these sheets. Please send to apharmdbattler@msn.com when you have a chance. Thank you for your time.

[mlemaire]

Hello eveyone,

I would also appreciate a copy of the spreadsheet for the f1 and f2 calculations. Please forward to my email below.

mmblemaire@hotmail.com

Best regards,

ML

[jlliberia]

Hello everyone,

I would also appreciate a copy of the f1 and f2 calculations spreadsheet. Please forward it to this email:

jlliberia@stegroup.com (mmblemaire@hotmail.com)

Thank you very much in advance for your help and best regards,

Josep Lluis Lliberia

[grreddy]

Dear Friends,

I have a validated excel sheet for calculation f1 and f2 those who wants send me u r mail ids as private msg . i will send it

[moff]

I just wanted to make a comment to everyone here regarding Excel. According to FDA, Excel spreadsheets need to be validated on individual computers or networks. I'm happy to see F1 and F2 spreadsheets getting around...just want to caution all of you to validate them at your sites, even if they've been validated from where they're coming from.

[HopeDeveloper]

i would also appreciate a copy of the f1 and f2 calculations spreadsheet.

[ialam]

Dear Friends,

I have a validated excel sheet for calculation f1 and f2 those who wants send me u r mail ids as private msg . i will send it

I would appreciate if you could send the validated spread sheet. I am very new to this and would like to understand the basics behind it. Please send me a private message with your email.
Thanks.

[SKV]

Yes, I do agree with the comment. As transfer from one location to other location the PC changes hence i think it is to be revalidated at the sites.

.