MGR ★ India, 20070202 11:10 (5899 d 21:57 ago) Posting: # 502 Views: 38,664 

Dear all, Please tell me about how to proceed for IVIVC using the pilot data. Also can anybody tell me the important tests and procedure for IVIVC Studies using WinNonlin or any software (SAS, SPSS,.....). If there are any important sites regarding IVIVC kindly let me know. Thanks and regards, MGR — Regards, MGR 
Helmut ★★★ Vienna, Austria, 20070207 20:56 (5894 d 12:12 ago) @ MGR Posting: # 510 Views: 38,131 

Dear Mamidi! ❝ Please tell me about how to proceed for IVIVC using the pilot data. OK, you are going in the right direction, namely starting with in vivo data! ❝ Also can anybody tell me the important tests and procedure for IVIVC Studies using WinNonlin or any software (SAS, SPSS,.....). Unless you want to start with parametric deconvolution, even M$Excel will do the job (I would not trust the builtin Solverroutine)… Kinetica offers templates for the ‘classical’ methods (WagnerNelson, LooRiegelman) and convolution/deconvolution. If you have already a little experience with WinNonlin’s programming language, it should not be too difficult to implement any needed model manually. An additional product (the IVIVC Tookit) is available for the latest release (5.2) of WinNonlin only. ❝ If there are any important sites regarding IVIVC kindly let me know. Not directly IVIVC, but browse through the archive at Dissolution Technologies, and have a look at this nice review. — Diftor heh smusma 🖖🏼 Довге життя Україна! _{} Helmut Schütz The quality of responses received is directly proportional to the quality of the question asked. 🚮 Science Quotes 
venu ☆ Mumbai, India, 20070223 07:58 (5879 d 01:10 ago) @ Helmut Posting: # 533 Views: 35,980 

Dear HS! I would like to share this piece of infomation which I am sure will be useful: http://www.dissolutiontech.com/DTresour/800Articles/800_art1.html Best Regards, Vandana Panchal — Best Regards, Ms. Vandana Panchal Biostatistician Mumbai India 
Dipesh Jayswal ● 20070316 08:53 (5858 d 00:14 ago) @ venu Posting: # 582 Views: 35,647 

Dear groupmates, can u please suggest the method for calculating "dose absorbed" at each sampling time point from Plasma concentration Vs Time profile of the subject from Bioequivalence study? Please suggest me the complete procedure with formula or some easily accessible reference on net. Thanks in advance, Dipesh Jayswal 
Helmut ★★★ Vienna, Austria, 20070316 16:39 (5857 d 16:29 ago) @ Dipesh Jayswal Posting: # 583 Views: 37,832 

Dear Dipesh! First of all get the two ‘classical’ papers; for the 1compartment model,^{[1]} and for the 2compartment model.^{[2]} ❝ Please suggest me the complete procedure with formula… Below is a simple example of the WagnerNelson method.
┌────┬──────┬───────┬───────┬───────┬──────┐ ❝ … or some easily accessible reference on net. A nice website is run by David Bourne. If you want to examine your own data you will need the Javaplugin for your browser; for examples on absorption see this one of David's pages and followings.
— Diftor heh smusma 🖖🏼 Довге життя Україна! _{} Helmut Schütz The quality of responses received is directly proportional to the quality of the question asked. 🚮 Science Quotes 
Dipesh Jayswal ● 20070319 11:04 (5854 d 22:03 ago) @ Helmut Posting: # 586 Views: 36,416 

Dear HS, Thanks a lot for ur detailed calculation. Regards, Dipesh 
drcampos ★ Brazil, 20070319 16:26 (5854 d 16:42 ago) @ Helmut Posting: # 587 Views: 35,724 

Dr. Helmut, I have just seen your explanation about WagnerNelson and LooRiegelman methods (model dependent approach). So, if possible, I would like to know how apply deconvolution approach to obtain fraction absorbed using excel. This method is known as modelindependent approach. Could you help me with details about calculations and articles about this topic? best regards, Daniel Rossi de Campos Brazil 
Helmut ★★★ Vienna, Austria, 20070319 17:20 (5854 d 15:48 ago) @ drcampos Posting: # 588 Views: 39,380 

Dear Daniel! ❝ So, if possible, I would like to know how apply deconvolution approach to obtain fraction absorbed using excel. This method is known as modelindependent approach. Could you help me with details about calculations and articles about this topic? First I would recommend two other ‘classical’ papers:
Langenbucher F. In vitro Prüfung und Korrelation mit in vivo Daten. In: Meier J, Rettig H, Hess H. Biopharmazie – Theorie und Praxis der Pharmakokinetik. Stuttgart 1981; Georg Thieme: pp 300–3. Main problems with numerical deconvolution are: Sampling points of the response function (e.g., an oral formulation), and the weighting function (i.e., an i.v. dose or an oral solution) must be equidistant, which they almost never are. Therefore you must interpolate ‘missing’ data points by a suitable algorithm (first approximation would be linear interpolation until T_{max}, and linear/log afterwards, better options are splines or Lagrangepolynoms). Numerical deconvolution is subject to instability such as sudden oscillations in the input function. Errors in early time points have a cumulative effect upon subsequent estimates. You may use my speadsheet as some kind of a sandbox: alter values, and watch… But please don’t use it for your actual problems! For the application of M$Excel in IVIVC have a look at Langenbucher F. Handling of computational in vitro/in vivo correlation problems by Microsoft Excel: III. Convolution and deconvolution. Eur J Pharm Biopharm. 2003; 56(3): 429–37. doi:10.1016/s09396411(03)001401. Software packages having a deconvolution module onboard (WinNonlin 5.2+, Kinetica, PDxIVIVC) rely heavily on smoothing of data – but manufacturers rarely document the actual method in the manual. Good look! — Diftor heh smusma 🖖🏼 Довге життя Україна! _{} Helmut Schütz The quality of responses received is directly proportional to the quality of the question asked. 🚮 Science Quotes 
drcampos ★ Brazil, 20070319 22:17 (5854 d 10:51 ago) @ Helmut Posting: # 589 Views: 35,835 

Helmut, Thank you for your prompt reply and the excelsheet with detailed calculation. Therefore, the articles suggested and the explanation were very important to understand the principle of the numerical deconvolution. I have just requested the IVIVC module of WinNonlin to Pharsight. Best regards, Daniel Rossi de Campos Brazil 
Rayhope ☆ India, 20211007 16:25 (538 d 17:42 ago) @ Helmut Posting: # 22621 Views: 3,146 

❝ You may use my speadsheet as some kind of a sandbox: alter values, and watch… Dear Daniel, Is your excel sheet still available to start with? it will be great if you can share it. Regards, Ray. 
Helmut ★★★ Vienna, Austria, 20211007 18:38 (538 d 15:30 ago) @ Rayhope Posting: # 22622 Views: 2,965 

Hi Ray, ❝ Is your excel sheet still available to start with? it will be great if you can share it. If you would have looked at Daniel’s profile, you would have noticed that the last time he logged in was nine years ago. You can try to send him a PM. No idea whether the email he used in registration is still current. If that doesn’t work, I can ask him (my last contact was in April). — Diftor heh smusma 🖖🏼 Довге життя Україна! _{} Helmut Schütz The quality of responses received is directly proportional to the quality of the question asked. 🚮 Science Quotes 
Rayhope ☆ India, 20211008 11:07 (537 d 23:01 ago) @ Helmut Posting: # 22623 Views: 2,869 

❝ If you would have looked at Daniel’s profile, you would have noticed that the last time he logged in was nine years ago. You can try to send him a PM. No idea whether the email he used in registration is still current. ❝ ❝ If that doesn’t work, I can ask him (my last contact was in April). Sure I will ask Daniel. Thank you. 
Rayhope ☆ India, 20211111 09:35 (503 d 23:33 ago) @ Rayhope Posting: # 22671 Views: 2,344 

❝ ❝ If that doesn’t work, I can ask him (my last contact was in April). Hi, I tried to contact Daniel but I guess not active here. Can you ask him please. 
Dipesh Jayswal ● 20070321 09:21 (5852 d 23:47 ago) @ Helmut Posting: # 590 Views: 35,994 

Dear HS, Please correct the year of the publication which u have prescribed in ur mail.
Regards, Dipesh 
Helmut ★★★ Vienna, Austria, 20070321 13:13 (5852 d 19:55 ago) @ Dipesh Jayswal Posting: # 591 Views: 35,599 

Dear Dipesh, oops, thank you for the correction! — Diftor heh smusma 🖖🏼 Довге життя Україна! _{} Helmut Schütz The quality of responses received is directly proportional to the quality of the question asked. 🚮 Science Quotes 
jesse08 ● 20070901 03:38 (5689 d 06:30 ago) @ Helmut Posting: # 1045 Views: 35,084 

Hi: Anyone know how to calculate the plasma profile using in vitro dissolution profile and IVIVC? i.e. in vivo absorption profile > plasma profile Thanks. HMY 
Helmut ★★★ Vienna, Austria, 20070901 16:49 (5688 d 17:19 ago) @ jesse08 Posting: # 1046 Views: 35,231 

Dear HMY! ❝ Anyone know how to calculate the plasma profile using in vitro dissolution profile and IVIVC? Yes. ❝ i.e. in vivo absorption profile > plasma profile This is the concept of ‘Mapping’. You should have all tools given previously in this thread handy. Once you have an IVIVC established, it’s trivial to calculate in vivo dissolution and therefore predict the plasma profile. What is your question? — Diftor heh smusma 🖖🏼 Довге життя Україна! _{} Helmut Schütz The quality of responses received is directly proportional to the quality of the question asked. 🚮 Science Quotes 
jesse08 ● 20070902 02:32 (5688 d 07:35 ago) @ Helmut Posting: # 1047 Views: 35,118 

❝ Once you have an IVIVC established, it’s trivial to calculate in vivo dissolution and therefore predict the plasma profile. ❝ What is your question? My question is once I have IVIVC, any software or program I can use to predict in vivo plasma profile (i.e. how to run the convolution? How to run the convolution in WinNonlin?) Thanks. HMY Edit: Full quote removed. Please see this post! [HS] 
Helmut ★★★ Vienna, Austria, 20070902 14:03 (5687 d 20:05 ago) @ jesse08 Posting: # 1048 Views: 35,382 

Dear HMY! ❝ My question is once I have IVIVC, any software or program I can use to predict in vivo plasma profile (i.e. how to run the convolution? How to run the convolution in WinNonlin?) In WinNonlin you have two options:
Links to other software are given in this thread; Kinetica has IVIVCTemplates ‘onboard’. — Diftor heh smusma 🖖🏼 Довге життя Україна! _{} Helmut Schütz The quality of responses received is directly proportional to the quality of the question asked. 🚮 Science Quotes 
jesse08 ● 20071003 04:13 (5657 d 05:55 ago) @ Helmut Posting: # 1150 Views: 36,254 

Hi: Did anyone compare the convolution results (i.e. predicted in vivo concentration profile) between Pharsight's IVIVC toolkit and MSExcel method by Langenbucher's article: Handling of computational in vitro/in vivo correlation problems by Microsoft Excel: III. Convolution and deconvolution? Are the results similar? I am using the MSExcel method now to do the convolution. I just want to make sure the IVIVC toolkit will produce the same results. HMY 
Nirali ★ India, 20071121 13:38 (5607 d 19:30 ago) @ jesse08 Posting: # 1316 Views: 35,087 

Dear HS, I have WinNonlin 5.2 version with IVIVC kit. For IVIVC comparison WinNonlin ask minimum three formulation for comparison. I have only two formulations on hand ! Has WinNonlin any other way to compare two formulations Thanks & Regards, Nirali 
Helmut ★★★ Vienna, Austria, 20071121 16:25 (5607 d 16:43 ago) @ Nirali Posting: # 1317 Views: 35,071 

Dear Nirali, ❝ I have WinNOnlin 5.2 version with IVIVC kit. How much did the IVIVC Toolkit cost? ❝ For IVIVC comparison WinNonlin ask minimum three formulation for comparison. You will need at least 3 data pairs for any type of linear dependency; this is not a WinNonlinproblem. Just imagine: In a linear regression you estimate two parameters – intercept and slope. With 3 data pairs, you have 1 degree of freedom left. With only 2 data pairs you have no degrees of freedom, or in other words you will always be able to draw a straight line, but getting no information on goodness of fit (coefficient of correlation = exactly one). ❝ I have only two formulation on hand ! Oh, that’s bad – no resolution possible, unless you come up with results from a 3^{rd} formulation… — Diftor heh smusma 🖖🏼 Довге життя Україна! _{} Helmut Schütz The quality of responses received is directly proportional to the quality of the question asked. 🚮 Science Quotes 
Nirali ★ India, 20071122 08:53 (5607 d 00:15 ago) @ Helmut Posting: # 1320 Views: 34,803 

Dear Helmut, Thank you. I will definitely get back to you if i have any query about IVIVC. ❝ How much did the IVIVC Toolkit cost? We purchase WinNonlin IVIVC toolkit in April 2007 and paid 3000$/user/single workstation. Warm Regards, Nirali 
Helmut ★★★ Vienna, Austria, 20071122 10:53 (5606 d 22:15 ago) @ Nirali Posting: # 1323 Views: 34,982 

Dear Nirali, yesterday I was too fast in responding. Of course you need ≥3 formulations only for Level BC correlations. If you were lucky enough to get a pointtopoint correlation (Level A), even one formulation (+iv data) is enough. — Diftor heh smusma 🖖🏼 Довге життя Україна! _{} Helmut Schütz The quality of responses received is directly proportional to the quality of the question asked. 🚮 Science Quotes 
Nirali ★ India, 20071127 07:05 (5602 d 02:03 ago) @ Helmut Posting: # 1335 Views: 34,834 

Dear Mr. Helmut, Yes you are right. I have little bit idea about level A correlation. I tried it in Excel using Wagner Nelson method. But here I am not able to perform IVIVC from WinNonlin due to lack of 3rd formulation. Is Level A correlation possible with WinNonlin? Then how? Friends, pls do share with me if you have exp of WinNonlin IVIVC. Thanks & Regards, Nirali 
SDavis ★★ UK, 20090925 11:11 (4933 d 22:57 ago) @ Nirali Posting: # 4248 Views: 33,559 

Nirali, Sorry to resurrect an old thread but I just saw your question about "For IVIVC comparison WinNonlin ask minimum three formulation for comparison" and I am not sure I see where you get that message  it is recommended to have a minimum of 3 but you can build one with the you have or even 1, although of course you will have difficulty having confidence to go extrapolate in the PREDICTION tab, but the first 3 stages will work fine, that is IN VITRO fitting, IN VIVO fitting and CORRELATION — Simon Senior Scientific Trainer, Certara™ [link=https://www.youtube.com/watch?v=xXyCO5Rzag[/link] https://www.certarauniversity.com/dashboard https://support.certara.com/forums/ 
sonu ☆ 20090923 10:47 (4935 d 23:21 ago) @ Dipesh Jayswal Posting: # 4234 Views: 33,413 
