Re: NONMEM error

> Op 5 dec 2024 om 20:45 heeft Dennis Fisher < > > [email protected] > > > het volgende geschreven: >  > > Colleagues > > I have encountered a problem during NONMEM execution. > > Most subjects are dosed daily but a small number of subjects have large intervals (> 30 days) between successive doses. > > For subjects dosed daily, concentrations 24 hours after a dose are BQL and there is no evidence of accumulation. > > For the problem subjects, NONMEM either: > > 1. aborts (despite a NOABORT option) with an error message at the first dose after the lengthy gap > > 2. or sends the following error message: > > 0PRED EXIT CODE = 1 > > 0INDIVIDUAL NO. 103 ID= 3.11040000000000E+04 (WITHIN-INDIVIDUAL) DATA REC NO. 56 > > THETA= > > 1.66E+02 1.15E-01 2.95E+01 1.81E+01 4.33E+01 3.01E+02 8.26E+00 0.00E+00 1.00E+00 0.00E+00 > > 0.00E+00 1.00E+00 1.00E+00 1.00E+00 1.00E+00 1.00E+00 1.00E+00 > > OCCURS DURING SEARCH FOR ETA AT INITIAL VALUE, ETA=0 > > NUMERICAL DIFFICULTIES WITH INTEGRATION ROUTINE. > > MAXIMUM NO. OF EVALUATIONS OF DIFFERENTIAL EQUATIONS, 1000000, EXCEEDED. > > The error occurs with METHOD=1 but NOT with METHOD=0. > > For one subject in whom doses were administered on Days 1, 30, and 60 (followed by daily dosing), I deleted the first two dosing records and the error no longer occurs with METHOD=1. I speculate that the error might relate to the predicted concentration becoming Infinitesimally small after a lengthy interval between doses, However, I have no idea if this is the explanation. And I am reluctant to change the dataset so I seek other solutions. > > Any ideas as to an explanation or a work-around? > > Dennis > > Dennis Fisher MD P < (The "P Less Than" Company) Phone / Fax: 1-866-PLessThan (1-866-753-7784) www.PLessThan.com