LANCASTER, CA, April 25, 2006 - Simulations Plus, Inc. (AMEX: SLP), a leading provider of simulation and modeling software for pharmaceutical discovery and development, announced that it has released version 5.1 of its gold standard GastroPlus (TM) software product. GastroPlus is the most widely used software in the industry for the simulation of oral absorption, pharmacokinetics, and pharmacodynamics, with customers throughout the U.S., Europe, and Japan.

Dr. Viera Lukacova, product manager for GastroPlus for Simulations Plus, said: "With this release, we have added a number of improvements to the PBPKPlus (TM) module that was released last December, including a very convenient Units Converter that enables scientists to input their in vitro metabolism and transporter data in their own units, convert them into the units and scaling needed within GastroPlus, and export them to the database with a mouse click. In addition, we've expanded the graphics and file output options in several ways, and improved the Virtual Trial feature when used with PBPK models. We've also added a powerful new function that allows formulation scientists to specify a particle size distribution for solid particles that must dissolve upon the disintegration of a tablet. This function required extensive modifications to the software to accommodate dividing up the particles that make up a dose into a series of mathematical "bins" that contain a certain percentage of the dose with a certain particle size. Real dosage forms are distributions of particle sizes - not all one size - and although the use of the average particle size approach we provided in the past worked for many drugs, this new feature is more general and will enable researchers to see how changing particle size distributions will affect the rate at which drug dissolves in the gastrointestinal tract."

Dr. Michael Bolger, director of life sciences for Simulations Plus, added: "It's a sign that you're doing something right when two of the largest pharmaceutical companies in the world ask you to modify your product to meet their needs. We received a request earlier this year from one of the major pharmaceutical companies to add the particle size distribution capability to GastroPlus. Shortly thereafter, another major pharma company made the same request. The speed with which this complex new capability was added is a tribute both to Dr. Lukacova and to the team effort that enabled us to take lessons learned from our DDDPlus (TM) development efforts and incorporate them into GastroPlus relatively quickly. As it happens, we also ended up improving DDDPlus in the process, and the new version 2.0 that we released earlier this month contains those improvements. Both of these releases are the culmination of a lot of hard work and diligence on the part of their product managers, with significant support from other team members as well."

About Simulations Plus, Inc.

Simulations Plus, Inc., is a premier developer of groundbreaking drug discovery and development simulation software, which is licensed to and used in the conduct of drug research by major pharmaceutical and biotechnology companies worldwide. The Company's Words+ subsidiary produces assistive technology and communication devices for persons with disabilities.  The Company also produces a line of educational simulation software under the umbrella name FutureLab™, which is based on its proprietary software technologies. Simulations Plus, Inc., is headquartered in Southern California. For more information, visit our Web sites at www.simulations-plus.com and www.words-plus.com.

Safe Harbor Statement Under the Private Securities Litigation Reform Act of 1995 - With the exception of historical information, the matters discussed in this press release are forward-looking statements that involve a number of risks and uncertainties. The actual future results of the Company could differ significantly from those statements. Factors that could cause or contribute to such differences include, but are not limited to: the ability of the Company to continue to book revenues and earnings in accordance with existing accounting standards, the ability of the Company to maintain its competitive advantage, the general economics of the disability and pharmaceutical industries, the ability of the Company to attract and maintain sufficient scientific and technical staff to sustain its R&D and customer support functions, and a sustainable market. Further information on the Company's risk factors is contained in the Company's quarterly and annual reports as filed with the Securities and Exchange Commission.


For further information:
Simulations Plus, Inc.
42505 10th Street West
Lancaster, CA
93534-7059 USA
www.simulations-plus.com
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Contact: Renee Bouche