Infectious Disease

Integrating broad scientific and medical expertise for end-to-end solution strategies

A multi-faceted approach is crucial on an individual and global-health scale. For us at Parexel, it is deeply rewarding to support our colleagues in the biopharmaceutical industry as they work tirelessly to meet this goal. We bring to bear our own extensive expertise in pathogen-driven studies and vast global experience in community healthcare, helping our clients develop comprehensive strategies for treating and preventing these complex life-threatening illnesses.

Parexel has developed a Long COVID Syndrome Program and Resource Center to address the long-term impact on COVID-19 subjects. We are working with sites, registries and patients across therapeutic areas to streamline research in this area. For these patients and their little-understood conditions, it is even more crucial than ever to listen to their voices, seating them at the head of the table to guide us toward meaningful outcomes.

Our dedicated infectious disease team has contributed to more than 600 trials in the past 5 years, including vaccines, antibacterial, antiviral, antiparasitic and antifungal compounds.

Our practice is distinguished by:
  • A team of public health professionals with global experience with crises including COVID-19, SARS, H1N1, MERS and Ebola. 

  • Strong experience working on 175+ COVID-19 treatments since January 2020, with recognition as a top-ranked CRO for COVID-19 clinical development services by the Life Science Strategy Group.

  • Long COVID Syndrome Program and Resource Center that includes an interactive tracking map showing vaccine updates and reported COVID cases. 

  • Access to all patient segments. We have developed methods for including study participants ranging from neonates to geriatrics, with exceptional skill in conducting hospital-based critical care studies, as well as outpatient and community venues, targeting a diverse population.

  • A global network of infectious disease research sites, including vaccine centers, decentralized community outreach, outpatient clinics, hospitals, and critical-care specialty centers.

  • End-to-end, integrated support from medical feasibility assessment through management of complex trials from Early Phase to Phase IV, post-marketing study commitments and market access.

  • Cross-functional expertise integrated into a holistic program-development approach. This includes regulatory affairs, real-world evidence, epidemiology, genomics, pulmonology, cardiology and any other relevant therapeutic areas across all age groups.

  • Deep understanding of the nuances of delivering trials for infectious disease with operational excellence. This includes a specific focus on microbiological and clinical endpoints, as well as long-term surveillance.

  • Lab-based work incorporating genomics, prognostic biomarkers and state-of-the-art diagnostics. 

  • Extensive expertise in hospital-based trials, crucial for trials involving surgical devices.

  • Close collaboration on global trials with academic researchers and partnerships with third-party funding organizations including governments (BARDA, NIH, EMA) and grants providers.  

Over the last 5 years, Parexel’s infectious disease and vaccine experience has included:


Conducting 650+ clinical projects


Enrolling 400,000+ patients


Working with 15,000+ sites


180+ infectious disease vaccine projects


We cover the full spectrum from hospital-based studies to community outreach, with special partnerships to reach patients in low-access healthcare areas that help increase subject diversity. During our years of involvement, we have developed deep understanding of a vast range of indications, as follows.

Viral Indications

Global experience with crises including COVID-19, SARS, H1N1, MERS and Ebola, as well as influenza, RSV, HIV/AIDS and hepatitis B and C.

Bacterial Indications

Specialized expertise in multi-drug–resistant infections (cIA, cUTI, HAP/VAP, ABSSI, joint infections, osteomyelitis).

Vaccines, Preventative and Treatment

Extensive work in COVID-19, influenza, pandemic vaccines, RSV, pneumococcal and meningococcal infections, combination vaccines for pediatrics, and dengue.

Critical Care

A global network of critical-care specialty centers with particular expertise in sepsis indications and nosocomial infections, and exceptional skill in hospital-based critical-care studies.



We are always available for a conversation.


We are always available for a conversation.


Communication Preference

Communication Preference