BIO
Liz Spehalski, Ph.D.
Principal Consultant, Regulatory Consulting
Explore end-to-end solutions throughout development — from portfolio optimization and regulatory strategy, to Phase I-IV clinical trials, market access planning, and more.
Our team optimizes your portfolio utilizing integrated expert clinical, regulatory, and market access strategies, enabling earlier and more informed risk-reward decisions.
Our multi-disciplinary early phase approach accelerates the path to proof of concept by integrating diverse expertise to optimize study design, generate robust clinical evidence, and reduce gaps between development phases.
We deliver whole-study solutions with integrated strategies that ensure safety, data integrity, and regulatory compliance. We design patient-informed protocols that remove participation barriers, accelerate enrollment, and increase the likelihood of successful drug launches.
Our team of former regulators and HTA professionals provide tailored regulatory, compliance, and market access strategies across specialized therapeutic areas, creating customized pathways to maximize global market reach throughout your product's lifecycle.
We enhance your product's value story through post-approval studies and holistic lifecycle management services that satisfy regulators and payers while building stakeholder trust and maximizing your drug's market impact throughout its entire lifecycle.
ParexelAI leverages our full suite of AI capabilities to deliver with greater speed, quality, and efficiency.

ParexelAI
ParexelAI is a proprietary AI-enabled clinical development suite that accelerates patient outcomes by combining Parexel's operational expertise with cutting-edge AI technology.
Utilize our expertise across therapeutic areas, combining innovative trial designs, leading clinical and regulatory expertise, global reach, and a passion for changing patient lives.
Our team delivers high-quality clinical trials through forward-thinking medical expertise across multiple indications by combining strategic insight with operational excellence to support programs of all sizes.
Our infectious disease and vaccines cro services help treat and prevent life-threatening illnesses. Learn how our team of experts can aid in any complex trial.
Discover our inflammation and immunology CRO services. We bring agile support and a unique MOA-driven model to inflammation and immunology.
Parexel is a leading Oncology CRO with more than 80 ex-agency regulators and nearly 2,500 sites globally. Learn more about our oncology indications.
As a leading neuroscience CRO, we leverage global site relationships, specialized resources, and indication-specific expertise to accelerate breakthroughs in neurological and psychiatric treatments for patients worldwide.
As a top hematology CRO, our integrated teams use advanced analytics and real-world evidence to optimize hematology trial outcomes, ensuring faster, more effective drug development.
Our experts help you stay at the forefront of the industry — and ahead of change.

Clinical Trialblazers
Step into the world of biotech leaders and hear the untold stories behind their journeys to bring breakthrough innovations to life.
Honest conversations with the experts shaping what's next
Thinking about joining a clinical trial? Learn the drug development process, what it’s like to participate, how to find a trial, and answers to frequently asked questions.
Clinical trials provide patients with access to innovative investigational treatments that advance medical research. Participation requires careful consideration that weighs both the benefits and risks.

Patient Stories
Clinical study participation represents a deeply personal decision with potentially far-reaching impact, as evidenced by these inspiring individual stories that highlight both the life-changing potential for participants and the broader advancement of healthcare for all.
We are one of the largest CROs in the world, speeding life-changing medicine to market by engaging patients With Heart™. Learn about who we are, what we do, and what we believe.
With decades of biopharmaceutical leadership experience and a deep dedication to patients, our executive team drives us forward in delivering better trials, faster.
Find key information on our policies, strategies, pay data, and more.
Explore end-to-end solutions throughout development — from portfolio optimization and regulatory strategy, to Phase I-IV clinical trials, market access planning, and more.
Our team optimizes your portfolio utilizing integrated expert clinical, regulatory, and market access strategies, enabling earlier and more informed risk-reward decisions.
Our multi-disciplinary early phase approach accelerates the path to proof of concept by integrating diverse expertise to optimize study design, generate robust clinical evidence, and reduce gaps between development phases.
We deliver whole-study solutions with integrated strategies that ensure safety, data integrity, and regulatory compliance. We design patient-informed protocols that remove participation barriers, accelerate enrollment, and increase the likelihood of successful drug launches.
Our team of former regulators and HTA professionals provide tailored regulatory, compliance, and market access strategies across specialized therapeutic areas, creating customized pathways to maximize global market reach throughout your product's lifecycle.
We enhance your product's value story through post-approval studies and holistic lifecycle management services that satisfy regulators and payers while building stakeholder trust and maximizing your drug's market impact throughout its entire lifecycle.
ParexelAI leverages our full suite of AI capabilities to deliver with greater speed, quality, and efficiency.

ParexelAI
ParexelAI is a proprietary AI-enabled clinical development suite that accelerates patient outcomes by combining Parexel's operational expertise with cutting-edge AI technology.
Utilize our expertise across therapeutic areas, combining innovative trial designs, leading clinical and regulatory expertise, global reach, and a passion for changing patient lives.
Our team delivers high-quality clinical trials through forward-thinking medical expertise across multiple indications by combining strategic insight with operational excellence to support programs of all sizes.
Our infectious disease and vaccines cro services help treat and prevent life-threatening illnesses. Learn how our team of experts can aid in any complex trial.
Discover our inflammation and immunology CRO services. We bring agile support and a unique MOA-driven model to inflammation and immunology.
Parexel is a leading Oncology CRO with more than 80 ex-agency regulators and nearly 2,500 sites globally. Learn more about our oncology indications.
As a leading neuroscience CRO, we leverage global site relationships, specialized resources, and indication-specific expertise to accelerate breakthroughs in neurological and psychiatric treatments for patients worldwide.
As a top hematology CRO, our integrated teams use advanced analytics and real-world evidence to optimize hematology trial outcomes, ensuring faster, more effective drug development.
Our experts help you stay at the forefront of the industry — and ahead of change.

Clinical Trialblazers
Step into the world of biotech leaders and hear the untold stories behind their journeys to bring breakthrough innovations to life.
Honest conversations with the experts shaping what's next
Thinking about joining a clinical trial? Learn the drug development process, what it’s like to participate, how to find a trial, and answers to frequently asked questions.
Clinical trials provide patients with access to innovative investigational treatments that advance medical research. Participation requires careful consideration that weighs both the benefits and risks.

Patient Stories
Clinical study participation represents a deeply personal decision with potentially far-reaching impact, as evidenced by these inspiring individual stories that highlight both the life-changing potential for participants and the broader advancement of healthcare for all.
We are one of the largest CROs in the world, speeding life-changing medicine to market by engaging patients With Heart™. Learn about who we are, what we do, and what we believe.
With decades of biopharmaceutical leadership experience and a deep dedication to patients, our executive team drives us forward in delivering better trials, faster.
Find key information on our policies, strategies, pay data, and more.
Work Experience
Prior to joining Parexel, Liz worked for over 6 years as a pharmacology/toxicology reviewer at the FDA in the Center for Drug Evaluation and Research’s (CDER’s) Division of Hematology Oncology Toxicology (DHOT). Liz has expertise in FDA regulations and review processes in early-stage nonclinical development including IND- enabling preclinical proof-of-principle study and GLP toxicology study design requirements, as well as in mid- to late- stage nonclinical development including chronic toxicology, DART, and carcinogenicity study design requirements. Since joining Parexel she has gained significant experience with the nonclinical development of cell and gene therapy (CGT) applications, including Initial Targeted Engagement for Regulatory Advice on CBER Products (INTERACT), pre-IND meetings, and IND applications.
Education
Liz holds a Ph.D. in cell and molecular pathology from the University of Michigan. She also holds a bachelor's degree in biology from Villanova University.
Blog
New FDA guidance on validation of new approach methodologies (NAMs): What you need to know
CTB Blog
Decoding FDA's new ‘plausible mechanism framework’ guidance: what drug developers need to know
Blog
UK's nonclinical roadmap: MHRA joins global regulatory shift toward NAMs with detailed goals and timelines
Blog
FDA's new ‘plausible mechanism pathway’: Transforming regulatory approval for personalized gene therapies
Blog
FDA guidances for development of oligonucleotide therapeutics: Key takeaways for sponsors
Blog
Advancing the transition from animal models to alternative methods: FDA's initiative and sponsors' opportunities
Blog
Key implications for nonclinical development: FDA guidance on human gene therapy products incorporating human genome editing
Blog
New FDA guidance on validation of new approach methodologies (NAMs): What you need to know
CTB Blog
Decoding FDA's new ‘plausible mechanism framework’ guidance: what drug developers need to know
Blog
UK's nonclinical roadmap: MHRA joins global regulatory shift toward NAMs with detailed goals and timelines
Blog
FDA's new ‘plausible mechanism pathway’: Transforming regulatory approval for personalized gene therapies
Blog
FDA guidances for development of oligonucleotide therapeutics: Key takeaways for sponsors
Blog
Advancing the transition from animal models to alternative methods: FDA's initiative and sponsors' opportunities
Blog
Key implications for nonclinical development: FDA guidance on human gene therapy products incorporating human genome editing
Learn More