Astellas Abandons Sjögren’s Syndrome Treatment – What It Means for Patients

Astellas Pharma has become the latest pharmaceutical company to withdraw from the development of a potential treatment for Sjögren’s syndrome, marking another significant setback for the autoimmune disease community. The company recently terminated its early-stage clinical trial for the investigational drug ASP5502. This decision highlights the ongoing challenges in developing dedicated medicines for a condition that currently lacks approved therapies targeting the underlying disease mechanism.

Termination of the ASP5502 Phase I Trial

In late March 2026, Astellas Pharma confirmed the termination of its first-in-human study involving ASP5502. The clinical trial, identified by the number NCT06544642, was a Phase I study designed to evaluate the effects of the drug in healthy adults and adults with primary Sjögren’s syndrome. According to industry reporting, the study was halted for strategic reasons amid pipeline prioritization.

ASP5502 is a STING inhibitor. The trial was intended to be the first time this specific compound was administered to humans. The primary aims of the study were to check the safety of ASP5502 and to assess how people tolerate the medication. Despite the termination, the registry information outlines the rigorous design that was planned before the decision was made to halt development.

Planned Study Design and Methodology

Before its termination, the study was structured to proceed in three parts. In Part 1, healthy men and women were scheduled to take tablets of ASP5502 or a placebo just once. The study utilized a placebo control, where the placebo looked like the ASP5502 tablet but did not contain any medicine. Different small groups of participants were assigned to take a lower to a higher dose of ASP5502 or a placebo sequentially.

The protocol also included specific measures to understand how the body processes the drug. One small group was designated to take tablets of ASP5502 or placebo with and without food to determine if food intake affects the drug’s processing. Following their dose, participants were required to stay in the medical center for a few nights. This confinement allowed researchers to conduct blood tests and other safety checks.

Cardiac monitoring was a significant component of the safety evaluation. Participants underwent electrocardiograms, known as ECGs, to check heart health. One of these checks involved having their heart continuously tracked during the first night, a process called telemetry. These details underscore the level of scrutiny applied to early-stage investigational drugs in this therapeutic area.

Understanding Sjögren’s Syndrome

Primary Sjögren’s syndrome is a condition where the body’s immune system attacks glands that produce fluids, such as the tear and saliva glands. This immune response leads to hallmark symptoms including dry eyes and a dry mouth. However, the impact of the disease extends beyond these primary symptoms. Patients may experience fatigue, joint pain and skin problems.

For many patients, these symptoms can be severe. While symptoms can be treated, there is an unmet need to treat the actual condition rather than just managing the discomfort. The lack of dedicated medicines remains a critical gap in care. Astellas Pharma’s withdrawal underscores the difficulty companies face in addressing this unmet need despite the high demand for alternative options.

Broader Industry Challenges

The decision by Astellas follows a similar move by another major pharmaceutical company. On Jan. 31, 2025, Novartis announced it was giving up on an anti-CD40 antibody intended to treat Sjögren’s syndrome. According to reporting from Fierce Biotech, Novartis discontinued the program due to the drug’s benefit/risk profile.

These consecutive exits from the Sjögren’s syndrome development space highlight the complexities involved in creating effective autoimmune treatments. Industry observers note that Sjögren’s is an underserved disease with a lot of patients who need alternative options. However, the strategic prioritization of pipelines by major firms suggests that the scientific or commercial hurdles remain substantial.

With the termination of the ASP5502 Phase I trial, the landscape for Sjögren’s syndrome research faces renewed uncertainty. Patients and advocates continue to wait for therapies that can address the root causes of the autoimmune disorder. Until new candidates emerge and succeed in clinical testing, the reliance on symptom management remains the standard of care.

Novartis gives up on anti-CD40 antibody to treat Sjögren’s due to ‘benefit/risk profile’

Fierce Biotech

The convergence of these developments indicates that while the need for treatment is clear, the path to approval is fraught with obstacles. As companies reassess their portfolios, the hope for a dedicated medicine for Sjögren’s syndrome remains deferred. The medical community continues to monitor the pipeline for any new entries that might succeed where recent candidates have not.