Treating pain in children at PAGE

27 June 2024

We are extremely proud to announce that Rik Schoemaker delivered his oral presentation at the PAGE meeting in Rome on 27 June 2024 on Quantification of the analgesic effect of intranasal coadministration of ketamine and sufentanil in adults to support the development of a pain relief treatment (CT001) in children with wonderful feedback from the audience! The pdf of the presentation can be downloaded here or from the PAGE website, and a pre-recorded presentation with audio can be downloaded here.

Occams in Rome at PAGE 2024

12 June 2024

Occams is proud to sponsor the PAGE meeting in Rome from 25-28 June, and we hope to see many of you there!

nlmixr2 workshop at PAGE

26 March 2024

The nlmixr2 team is delighted to announce that it will be running another nlmixr2 workshop prior to PAGE in Rome on Tuesday 25 June 2024 (13:00-17:00, at the PAGE conference hotel) hosted by Occams. The course will consist of a mixture of lectures and hands-on exercises. nlmixr2 and its satellite packages (including rxode2 and a range of tools facilitating seamless interaction with other industry-standard tools like NONMEM and Monolix) are undergoing continuous and intensive development, and are intended to provide a complete suite of packages for pharmacometric data analysis as free, open-source software. nlmixr2 is based in R and provides robust support for parameter estimation (primarily through the SAEM and FOCEi estimation methods) and simulation. Places are limited and can be reserved here.

Advanced modelling workshop nlmixr2

14 June 2023

nlmixr2/rxode2 will be the centerpiece of a two days symposium, hosted by the PopSim Board (Danish Pharmaceutical Society) and the University of Copenhagen Drug Research Academy (DRA). Beginners and more advanced modellers will have the opportunity to work with nlmixr2/rxode2 during two workshops on the 15th and 16th of June. Having access to open source software like nlmixr2/rxode2 is a great opportunity for introducing population pharmacokinetic modeling and simulation to interested scientist who may otherwise not have had access. The advanced course on the afternoon of 16 June will be presented by Rik Schoemaker and Theodoros Papathanasiou, and course material is available from the nlmixr2 blog.

Occams in A Coruña at PAGE 2023

14 June 2023

Occams is proud to sponsor the PAGE meeting in A Coruña from 27-30 June, and we hope to see many of you there!

Occams seven years!

1 November 2022

We've just passed our 7-year anniversary, and what a journey it's been! From 2015, when we took that first leap of faith into the unknown, to now, having built a reputation for quality and reliability that remains virtually unmatched, it’s been not so much a trip, as an adventure with friends so close they’re like family. With offices in Germany, the Netherlands, Sweden and the UK, we are a closely-knit team of highly-experienced and highly-motivated pharmacometricians, laser-focused on the drug development questions that matter, with the skills to answer them effectively, on time and on budget. The best thing about being able to say this is that you don’t have to take our word for it – you can just ask some of those we’ve worked with.

It feels as fresh, and fun, and rewarding as the day we started. We feel like the best team in the world doing the best job in the world. Here’s to the next seven years, and the next seven after that.

OCCAMS at ACoP13 in Denver

26 October 2022

Jan-Stefan van der Walt and Justin Wilkins will be at ACoP13 in Colorado!

This is an especially cool ACoP for us, since Justin will be officially inducted as an ISoP Fellow during the Opening Ceremony on Sunday 30 October.

A former President of ISoP and a member of its Board of Directors from 2016-2021, Justin remains an active member of ISoP and we are proud that he has been selected for so great an honour. Hope to see you there!

We are the fabulous five!

1 August 2022

We are extremely happy to announce that Jan-Stefan van der Walt has joined the Occams family, effective 1 August 2022. Jan-Stefan brings a wealth of academic, industry, and medical experience across a broad range of indications, transforming our dream team to the fabulous five! Welcome aboard, Jan-Stefan!

Occams in Ljubljana at PAGE 2022

15 June 2022

Occams is proud to sponsor the PAGE meeting in Ljubljana from 28 June-1 July, and we'll all be there in person!

Rik Schoemaker and Justin Wilkins will be co-organizing an nlmixr2 course on 28 June - we hope to see many of you there!

Occams in Leiden at QSPC2022

20 April 2022

Occams is proud to sponsor the QSPC2022 meeting in Leiden from 20-22 April, and Rik Schoemaker will be attending; looking forward to finally catching up with old and new friends again!

Occams in Cape Town at WCoP2022

29 March 2022

Occams is proud to have sponsored the WCoP2022 meeting in Cape Town from 29 March-1 April. Julia Winkler, Justin Wilkins , and Rik Schoemaker attended, and were witness to an amazing conference and the finest opportunity to connect to real people again!

William of Ockham flees Avignon

26 May 2020

From Wikipedia, on this day in 1328: English friar William of Ockham, who popularised the methodological principle known as Occam's razor, secretly left Avignon under threat from Pope John XXII.

nlmixr comparison paper published

19 November 2019

Occams is extremely proud to be part of the nlmixr team that has just published a landmark comparison paper between the nlmixr/FOCEI and NONMEM/FOCEI algorithms, and between the nlmixr/SAEM and Monolix/SAEM algorithms. nlmixr is a free and open-source R-package that implements non-linear mixed effect modelling, and this publication now demonstrates that in both sparse and rich data situations, nlmixr can provide parameter estimates that match those obtained from the industry standards. The paper has been published in CPT:PSP and is now available in early view: Performance of the SAEM and FOCEI Algorithms in the Open-Source, Nonlinear Mixed Effect Modeling Tool nlmixr with Rik Schoemaker as first author, and Justin Wilkins as one of the co-authors.

nlmixr course Queenstown

11 September 2019

Rik Schoemaker will be presenting an nlmixr course in the form of the Intermediate Population Approach workshop as part of the ASCEPT-PAGANZ joint meeting in Queenstown, New Zealand on 25 November 2019. More information can be found here, and full course materials can be downloaded here.

nlmixr workshop at PAGE

15 February 2019

The nlmixr team is delighted to announce that it will be running another nlmixr workshop at PAGE in Stockholm on Tuesday 11 June 2019. Recent updates incorporating a solid FOCE-I algorithm greatly enhance the applicability of the R-based free and open-source package for non-linear mixed effect modelling! Places are limited and can be reserved here.

Simultaneous PK and PD modelling at PAGANZ in 2019

9 February 2019

To commemorate the 20th anniversary of PAGANZ, Janet Wade -as one of the original speakers at the founding conference- was invited to PAGANZ 2019 in Auckland to revisit her talk on simultaneous estimation of PK and PD. You can find her presentation here.

EMA recommendation using OCCAMS' work

26 November 2018

We are pretty proud to see our work being used in an EMA recommendation on How should results/predictions of pharmacokinetic analyses be presented to facilitate decision making about the adequacy of the proposed dosing regimen in paediatric patients? referencing Brivaracetam population pharmacokinetics in children with epilepsy aged 1 month to 16 years by Rik Schoemaker, Janet Wade and Armel Stockis, in the European Journal of Clinical Pharmacokinetics.

Occams at ACOP9 in San Diego

27 September 2018

Justin, Janet and Rik will be attending ACoP9 in San Diego from 7 to 11 October 2018. We anticipate, with great pleasure and pride, to see Justin start his year as President of ISoP.

In addition, Justin and Rik will be assisting with the first ACoP-sponsored nlmixr tutorial on Thursday 11 October (8:00AM-12:00PM).

We look forward to seeing and talking to all our friends and colleagues!

Occams in Montreux

10 May 2018

We are all attending PAGE in Montreux from 19 May to 1 June 2018! Justin and Rik will be assisting with the first European nlmixr workshop on 18 May, and we will be presenting two posters:

  • I-59: Population pharmacokinetic analysis of M7824 (MSB0011359C) in different cancer types, by Justin and colleagues
  • II-32: Drug-disease model describing the effect of intraarticular injected sprifermin on cartilage thickness measured by magnetic resonance imaging in osteoarthritis patients, by Julia, Rik and colleagues

nlmixr presentation at Pharmacometrics Network Benelux

27 March 2018

Rik Schoemaker will be presenting an overview of RxODE and nlmixr software developments at the 12th meeting of the Pharmacometrics Network Benelux in Groningen, the Netherlands on 29 March 2018. The slides can be found here.

nlmixr workshop at PAGE

15 December 2017

The nlmixr team is delighted to announce that it will be running an nlmixr workshop at PAGE in Montreux on Tuesday 29 May 2018! Registration will open January 15th 2018. Mark your calendar; places are limited and can be reserved here.

OCCAMS and Posters at ACoP8

11 October 2017

The entire Occams team will be present at ACoP8 in Ft. Lauderdale, and we will be presenting three posters:

Rik will be presenting a poster on Tuesday on nlmixr: an open-source package for pharmacometric modeling in R (T-012). This poster will be part of the Poster Spotlight session to highlight the integration between statistics and pharmacometrics.

Justin will be presenting two posters on Wednesday on Clearance over time and effect of response in the pharmacokinetics of avelumab (W-079) and Population pharmacokinetic analysis of avelumab in different cancer types (W-080).

Justin Wilkins is President-Elect of ISoP

22 September 2017

We are thrilled that our own Justin Wilkins has been announced as President-Elect of the International Society of Pharmacometrics (ISoP)!

Justin has served as a member of the ISoP Board of Directors since 2016. During this time, he has served as Secretary and a member of the Executive Committee, the chair for the Standards and Best Practices Committee, chair-elect for the Nomination Committee, and as leader or key contributor for several ISoP initiatives. Justin will succeed Jin Yan Jin as President-Elect at the end of ACoP8 (October 2017), and will start his Presidential term at the end of ACoP9 (October 2018).

Occams in Budapest

4 June 2017

We are all attending PAGE in Budapest from 6 to 9 June 2017! Come and see our posters:

  • II-03: nlmixr: an open-source package for pharmacometric modelling in R, by Rik, Justin and colleagues
  • II-49: Population PK analysis of Sym004 and the influence of variations in base model structure on covariate model building, by Janet, Rik and colleagues

The presenters will both be by their posters between 15:10 and 16:40 on Wednesday 7 June - come visit us!

Thoughtflow published!

31 May 2017

In collaboration with DDMoRe, Justin Wilkins and colleagues have published a white paper describing the new Thoughtflow standard for facilitating provenance-based capture, storage, and reporting of knowledge, including assumptions and decisions, as well as supporting reproducibility in pharmacometrics.

Visit the Thoughtflow community group here!

Rik Schoemaker wins the 2017 ISoP Leadership Award!

7 April 2017

We are proud to announce that our very own Rik Schoemaker is the 2017 recipient of the International Society of Pharmacometrics (ISoP) Leadership Award!

This award recognizes outstanding and sustained leadership, mentorship, and outreach contributions to the field of pharmacometrics and to the development of the strategic vision for the future direction of the field. The award will be presented at the opening of the ACOP8 meeting in Fort Lauderdale, Florida, on Sunday, 15 October, 2017, which we will all be attending. Rik is in good company - previous winners of this distinguished award include such luminaries in our field as Sandy Allerheiligen, Larry Lesko, Richard Lalonde, Hartmut Derendorf, William Jusko and David D’Argenio.

Rik is the heart and soul of PAGE, having overseen the organization of Europe’s pharmacometrics conference since 1996. Instrumental in shaping its sharp focus on science and its long tradition of supporting student research, Rik has been key in the development of an untold number of our past, present and future peers. It is safe to say that PAGE, and indeed the field of pharmacometrics in general, would not be what it is without him. If this were not enough, Rik is author and co-author of over 170 publications, including a number of original research articles, and is a key part of the team behind nlmixr, a new tool being developed for nonlinear mixed-effects modelling. If there is a more deserving candidate for the ISoP Leadership Award in 2017, we are hard pressed to think of one. Congratulations, Rik!

Occams has a new home

22 December 2016

We have secured a new domain and Occams now sits maturely at Our email addresses will be updated shortly, but you will still be able to contact us using the extension!

nlmixr and ACoP7

21 October 2016

Occams is very proud to be playing a supporting role in the release of nlmixr, an open source package for population PK and PKPD modelling developed by Wenping Wang and Yuan Xiong. nlmixr builds on Wenping's RxODE package for simulation of nonlinear mixed effect models using ordinary differential equations, by implementing parameter estimation algorithms like nlme, gnlmm and SAEM. nlmixr greatly expands the utility of existing packages (like nlme) by providing an efficient and versatile way to specify pharmacometric models and dosing scenarios, with rapid execution due to compilation to C++.

The source is now available at along with a vignette, and the models and datasets used in the nlmixr/nlme poster to be presented at ACoP (W-66): nlmixr: an open-source package for pharmacometric modelling in R on Wednesday, 26 October, 2016, 7:30-9:30 am. At this point, nlmixr is still very much in a testing stage and is under lively development. Get in touch, see us at ACoP to discuss ways you could contribute (Wenping Wang, Yuan Xiong, Justin Wilkins and Rik Schoemaker will all be there), or try it out for yourself, and experience the joy of a population modelling package within R! A live demo will be possible, so come see Rik if you are interested!

WCoP 2016 and nlmixr

17 August 2016

Occams will be represented at WCoP 2016 in Brisbane by Rik Schoemaker. Meet him there or come see his poster on nlmixr: an open-source package for pharmacometric modelling in R on Monday, 22 August, 2016, 12.15-1:15 pm. nlmixr is a highly exciting open-source development that allows non-linear mixed effect modelling using R and the nlme package, but implementing full dosing flexibility along with ordinary differential equations, and computational speed by compiling to C. A live demo will be possible, so come see Rik if you are interested!

Two new publications

27 July 2016

At Occams we believe in providing academic output next to our consultancy work, and we are therefore happy to announce that we have co-authored two publications over the last months:

Two oral presentations at PAGE

8 April 2016

We are extremely proud and honoured that Occams is has been granted two oral presentations at PAGE 2016! One will be presented by Lutz Harnisch (Pfizer) in a collaborative project with Pharmetheus, Occams and Pfizer with the title Modelling and simulation of neurological endpoints (modified Rankin Scale [mRS] and National Institute of Health Stroke Scale [NIHSS]) to aid clinical trial design in intracerebral hemorrhage (ICH), and one will be presented by Rik Schoemaker (Occams) with the title Extrapolation of a Brivaracetam Exposure-Response Model from Adults to Children on work performed while at Exprimo in collaboration with UCB.

Healthy Birth, Growth and Development Hackathon

7 April 2016

The Bill & Melinda Gates Foundation is organising a Healthy Birth, Growth and Development Hackathon prior to PAGE, and Rik Schoemaker will be representing Occams. Will you join us? The networking reception from 6-9PM on Sunday 5 June is free for all! Sign up here.

Sponsorships in 2016

3 March 2016

Occams is committed to supporting global training, research and development in the field of pharmacometrics. Our consultants are variously associated with PAGE and the International Society of Pharmacometrics (ISoP), and in 2016 we are proud to be sponsors of PAGE (, WCoP ( and PMX Benelux !

...and then there were three!

16 November 2015

We are extremely proud and happy to announce to the world that the Occams team has been extended with both Janet Wade and Justin Wilkins!