Dear IBBS Colleagues,
We regretfully wish to announce the passing on June 18, 2024 of Professor William (Bill) Pardridge, longtime faculty member at the UCLA School of Medicine and founder of the CNS drug delivery company Armagen.
Bill was an extremely important member of our field for over 40 years, during which time he was among the most highly recognized world experts in BBB / CNS delivery science and a trailblazing pioneer in academic entrepreneurship. For decades, Bill's review articles were often among the first papers new PhD students would read when embarking on research related to the CNS barriers or drug delivery to the brain. Bill was a deeply intelligent man with highly varied interests spanning biology, physiology, pharmacology, medicine, and other subjects. He was someone to always be taken very seriously and learn from, both for the breadth of his ideas and for his high volume scholarship. Bill was also way ahead of his time as an academic with respect to founding a company, patent strategies, and commercialization considerations. Bill was a truly unique scientist, among the sharpest minds in the field, and such a prolific scholar that his passing can only be properly viewed as the 'end of an era.' On behalf of the IBBS community, we send our sincere condolences to his family, friends, and collaborators.
IBBS Executive Leadership (Robert, Britta, Elga, and Les)
[Remembrance below kindly provided by his longtime colleagues Ruben Boado, Ulrich Bickel, and Rachita Sumbria]
With profound sorrow, we announce the passing of Dr. William M. Pardridge on 18th June, 2024. Known affectionately as Bill, he was not only an esteemed scientist but also a cherished friend and mentor to many within our community. Bill completed his bachelor’s degree in chemistry from the University of California, Los Angeles (UCLA), and an MD degree from Pennsylvania State University. After completing his residency in Internal Medicine at Boston University Medical Center, Bill returned to UCLA Medical Center for a fellowship in Endocrinology and Metabolism. He stayed at UCLA as an Assistant Professor of Medicine and was promoted to Full Professor of Medicine in 1985. Bill spent more than four decades studying the blood-brain barrier (BBB) until retiring from UCLA in 2013 as Distinguished Professor Emeritus.
Undoubtedly, Bill was a highly regarded scientist in the field and his legacy includes over 500 publications, numerous patents, and a lineage of postdoctoral trainees who continue to advance the field. Bill supported his work with innumerable research grants awarded by the NIH and other public institutions and private foundations. To name a few, Bill was the director of the NIH Program Project entitled "Biology of the Blood-Brain Barrier" and the NIH Neuroscience Training in Blood-Brain Barrier Research, which ran for 10 years. Bill made a name for himself in the 1980s by a series of elegant studies
exploring the role of protein binding of hormones and drugs on brain uptake. Bill’s focus shifted in the late 1980s to investigate the molecular biology of the BBB, specifically on the regulation of nutrient transporters (i.e.: BBB-specific glucose and large neutral
amino acids facilitated transporters, respectively). His work was also expanded to the BBB genomics and proteomics, and to the use of receptor-mediated transport mechanisms at the BBB as a novel drug delivery strategy. His lab published pioneering proof of principle studies, demonstrating that antibodies to the transferrin receptor or to
the insulin receptor can transport neuroactive drugs and biologics otherwise unable to cross the BBB, resulting in pharmacological activity in vivo. Not uncommon for truly innovative ideas, which are far ahead of their time, the concept, later known as the “molecular Trojan horse” strategy, was initially met with widespread skepticism.
Nevertheless, Bill’s tenacity and scientific rigor allowed him to continue producing high-quality peer-reviewed publications and he ended up founding the biotech company ArmaGen in 2003. His vision was transforming neurological disease treatment, a dream
he pursued relentlessly for the next 20 years. Bill focused his effort on realizing this dream and completed the genetic engineering of brain penetrating fusion proteins of antibodies against receptors expressed at the BBB and therapeutic proteins, for the treatment of Alzheimer’s, Parkinson’s, stroke and lysosomal storage disorders. His work in this field culminated in a positive phase I/II clinical trial in Hurler MPSI disease with a brain penetrating fusion protein comprised of an antibody to the human insulin receptor and iduronidase. Today, this approach to delivering drugs to the brain is widely investigated in academics and in the biotech industry, and gained market approval in Japan in 2021 for Hunter MPS II disease.
After retiring from UCLA, Bill continued to work on the Trojan horse approach and founded The Lipogene Company in 2016, where he focused on gene delivery using the Trojan horse liposome technology, until 2020. Bill retired from bench work in 2020, and
began avidly writing and publishing about his learnings to the scientific community from 2020-2024. His commitment to mentoring the next generation of scientists was unwavering, and those who were in touch with Bill during this time will attest to what an
exceptional mentor and human being he was. In his work, he was extremely well organized, mapping out future projects, manuscripts, and grant applications years in advance. He was blessed with a superb memory and had an encyclopedic knowledge of the scientific literature in his own and related areas. Over all the years leading his lab, he literally knew every single experimental detail and every figure and table in manuscripts submitted for publication. He thus served as an impeccable role model in scientific integrity to all his group members and collaborators. Those who were fortunate to know Bill will attest to his creativity and brilliance as a scientist with a keen desire to translate his efforts onto the bedside. However, Bill’s intellectual curiosity was not just confined to science. As a case in point, he became interested in the stock market as a college student, and by his own account, the interview for Medical School revolved mostly around stocks. Commuting to work he would listen to audiobooks on philosophers, and in his office, he had Minard’s map
showing Napoleon’s disastrous invasion of Russia hanging above his desk. Bill's impact is immeasurable. To phrase it with the words of his mentor Bill Oldendorf, one of the giants in neuroscience in the 20th century, who reportedly once answered to the question of what his greatest discovery was: Bill Pardridge. His memory will continue to inspire. As a brilliant scientist, a loyal friend, and a generous mentor, he has left a void that will be deeply felt by all who knew him. We express our sincerest condolences to Bill’s wife, Rhonda, to his sons, Robert and Charles, and to the rest of his family, friends, and colleagues.