Neuroimmunology pioneer and professor Michal Schwartz this summer took a step closer to finding a new treatment for Alzheimer’s Disease, and potentially other neurodegenerative diseases.
With nearly 1,000 scientists and doctors attending the July Alzheimer's Association International Conference in London, her team released the results of the first in-human clinical trial of their novel approach, using a drug called IBC-Ab002. It coincided with publication of a peer-reviewed article in the medical journal, Nature Medicine.
Francis Collins, a prominent physician-geneticist who served as director of the National Institutes of Health under three presidents from 2009 to 2021, says he is encouraged by the study.
“It represents a radically different approach
than anything that has been tried before, and that’s just what the field has needed,” Collins said.
The toppling of a dogma
For much of modern medical history, scientists regarded the brain as largely isolated from the peripheral immune system circulating in the blood.
That view was shaped by the work of some of the greatest figures in biology and medicine, including Santiago Ramón y Cajal, Paul Ehrlich and Peter Medawar. Their discoveries established modern neuroscience, immunology and pharmacology. Their work, however, also contributed to the flawed concept of the brain as “immune privileged,” a protected organ separated from ordinary immune activity by the “blood-brain barrier.” This concept, taught in medical schools for generations, had the effect of delaying research into the immune system’s potential role in the brain.
In a May 2026 article in the scientific journal Neuron, Schwartz described how the research she initiated, advanced by other scientists during the past three decades, has transformed that understanding. The brain, she wrote, is not a sealed citadel, but part of a “dynamic ecosystem” in which the nervous and immune systems work together to support resilience and repair.
That is the paradigm shift underlying her novel treatment for Alzheimer’s Disease.
In May 2024, I wrote a column for lohud.com, The Journal News and USA TODAY Network about the search for an immunotherapy approach to the treatment of Alzheimer’s Disease. For two decades, pharmaceutical companies have spent billions of dollars on the “amyloid hypothesis,” with drugs targeting the abnormal protein deposits —called amyloid plaques and tau — that accumulate in the brains of Alzheimer’s patients. While the latest anti-amyloid drugs modestly slow the disease in some patients, they carry serious side effects. Schwartz’s team has pursued a fundamentally different strategy: restoring communication between the aging brain and the body’s immune system, enabling that system to clear senescent cells that have lost function, as well as other toxic compounds associated with inflammation and neurodegeneration. This approach aims to rescue neurons, the specialized nerve cells in the brain that receive, process, and transmit electrical and chemical signals that are the building blocks of memory.
Releasing the immune system’s brakes
Schwartz conducts her research at Israel’s Weizmann Institute of Science, listed among the world’s top ten research institutions. She co-founded ImmunoBrain Checkpoint, the biotechnology company that developed the experimental drug IBC-Ab002.
The drug is a monoclonal antibody that disables an immune system checkpoint called PD-L1. Blocking the checkpoint releases the natural “brakes” that restrain the immune system. As reported in the Nature Medicine article,
“In aging, and increasingly in AD [Alzheimer’s Disease], the peripheral immune system becomes compromised leading to a self-perpetuating cycle in which exhausted, inflammation-promoting cells in the brain are no longer counterbalanced by an effective protective systemic immune response.”
Testing in mice
Her laboratory first tested the approach in mouse models of Alzheimer’s Disease. In peer-reviewed studies begun a decade ago, the treatment not only slowed disease progression but arrested and even restored some cognitive function in the animals.
Success in animals, of course, does not guarantee success in people. Many treatments that appear promising in laboratory animals subsequently fail in clinical trials.
PD-L1 checkpoint inhibitors used in cancer
For 20 years, medicines containing immune checkpoint inhibitors, such as PD-L1, have revolutionized the treatment of some cancers by enabling the body’s immune cells to attack malignant cells. Schwartz theorized that a carefully controlled form of checkpoint inhibition can jump start the immune system in the diseased brain, allowing it to resume removal of dysfunctional cells and other harmful material.
IBC-Ab002 was tailored for Alzheimer’s, which differs from checkpoint inhibitor drugs used in cancer treatment. In oncology, the prevailing method is to maintain continuous exposure to these drugs, as the immune system attacks rapidly reproducing malignant cells. In Alzheimer's Disease, however, the proposed mechanism of action suggests that only short, intermittent exposure is needed.
IBC-Ab002 was administered at different doses only once every three months to patients with early Alzheimer’s, and disappeared from the blood within about four days, acting more like a vaccine.
“Our drug is short-lived by design,” she explained. “Its purpose is to briefly stimulate the body’s immune response, enabling it to harness immune cells needed to help the brain eliminate senescent cells and other damaging material, rather than keeping the immune system continuously activated.”
What the first human trial found
The primary mission of a Phase 1b clinical trial is to determine whether an investigational drug appears safe and tolerable — not whether it cures or even slows a disease.
In that respect, the early results were encouraging. IBC-Ab002 was reported to be generally well tolerated by the patients who received it, with no treatment-related serious adverse events.
In addition, most patients receiving the highest dose showed meaningful reductions across a panel of biomarkers found in cerebrospinal fluid, including neurogranin, total tau and phosphorylated tau 181. These biomarkers are associated with damage to neurons, and may indicate that the drug is counteracting the disease process.
But biomarkers are not the same as demonstrated improvements in memory, reasoning or everyday functioning. The Phase 1b trial was small (40 patients), and it was too short (48 weeks) to prove clinical efficacy. Approval of a drug from the FDA will require much larger and longer Phase 2 and 3 clinical trials.
The significance of this trial is that an entirely different scientific theory has now moved from laboratory research and successful animal studies into human testing—and has produced enough evidence to warrant the next stage.
If larger studies eventually show that the approach restores cognitive ability, it could represent more than an Alzheimer’s drug. It could open a new path for treating other diseases associated with aging and neuroinflammation, such as Parkinson’s and Huntington’s Disease.
Collins, who recently joined the board of ImmunoBrain, cautions that the drug must demonstrate improved memory and mental function for patients in Phase 2 and Phase 3 trials. Asked whether the Phase 1b results warranted investment in those larger studies, Collins did not hesitate.
“Absolutely,” he replied, “and if there is ever a time to take a brand-new, novel approach that has a lot of compelling animal data and push the accelerator down, this feels like it.”
Alexander Roberts is a former New York City television news reporter and founder and CEO emeritus of the nonprofit Community Housing Innovations, based in White Plains, New York.
This article originally appeared on Rockland/Westchester Journal News: There's a new way to tackle Alzheimer's. It's encouraging | Opinion
