Hello, I just tried to implement a literature model to test additivity of co-administrated anticancer drugs into Phoenix 6.2. (Rocchetti et al. 2009). This model consists of 7 parameters and 17 differential equations. I’m getting the error message: Error in Population: Error: Number of differential equations (17) times number of random effects (6 + 1) exceeds limit of approx. 100. Der Befehl “”.\NLME7.exe"" ist entweder falsch geschrieben oder konnte nicht gefunden werden. Model execution failed or cancelled If I reduce the number of parameters and replace them by fixed statements, the model runs, but that’s obviously not what I would like to do. Does anybody has any suggestions or workarounds ?
Cornelia, Which version of Phoenix are you using? There were some restrictions previously but I thought most of those had been raised. Is it possible you can post the project (or email it to support@pharsight.com) so we can investigate further. Simon.
Hi Simon, I’m running version 6.2. I attached the project below. Thanks for your help, Conny [file name=Rocchetti_additive.phxproj size=665285]Certara | Drug Development Solutions (650 KB)
Cornelia - this code executes in 6.3 without that error message. Note that in you present code you have not set initial estimates, remember in textual mode they need to be transferred manually to this section. fixef(tvk1a = c(, 1, )) fixef(tvk1b = c(, 1, )) fixef(tvk2a = c(, 1, )) … also I just wanted to check, this was a repeated dose study right? doses every 96 h or thereabouts? I suggest you get the 6.3 version (released in March) and work with that, page 18 of the release notes covers your limitation; Error: Number of differential equations (5) times number of random effects (28 + 1) exceeded limit of approximately 100 (QC 10923): The generation of sensitivity equations is now done only when needed, in order to not balloon the number of ODEs. This error message should only occur now when the limits are truly exceeded. Simon. For what it’s worth here are the first few lines of the run with the default initial estimates. # Population: # NLME7 built Mar 19 2012, 11:59:42 # ODE level: requested, used = 6, 3 # ODE levels: 6=matexp, 5=LSODA(ana jac), 4=LSODA(num jac), 3=RK, 2=stiff(ana jac), 1=stiff(num jac), 0=none ReturnCode = -1 LLLaplace = 72.88710 EpsShrinkage = -2.66014 NParm = 13 NObs = 40 NSub = 4 fixed effects theta[0] = 0.00216687 # tvk1a theta[1] = 2.66264 # tvk1b theta[2] = -6.31396e-006 # tvk2a theta[3] = 2.45986e-005 # tvk2b theta[4] = -0.261383 # tvlamda0 theta[5] = -0.00164338 # tvlamda1 theta[6] = 0.0270697 # CEps