When a gene therapy sponsor pauses a clinical program, the operational machinery responds within hours. The medical monitor convenes a safety review. Regulatory affairs begins drafting the FDA notification. The data monitoring committee meets in closed session.
On the other side, the patients learn about it differently. Dozens of clinical sites each have individual conversations with enrolled participants, using whatever language their principal investigators choose. Patient advocacy groups, monitoring the sponsor's earnings calls and press releases, relay often fragmented information to their communities, while caregivers turn to social media for clarity. Somewhere, a parent whose child received a one-time gene therapy dose three months ago reads a headline.
The sponsor has activated its Rapid Response Team and has a crisis communication playbook ready to execute. What it does not have is a coordinated, pre-built communication layer capable of reaching every patient, caregiver, site coordinator, and advocacy group simultaneously with consistent, IRB-reviewed information.
This is the structural gap in gene therapy development. The field has invested heavily in manufacturing, vector design, and regulatory strategy. It has underinvested in the communication infrastructure required to maintain trust when that trust is tested most.
Gene therapy clinical holds are sometimes discussed as rare, exceptional occurrences. The data tells a different story.
A 2023 analysis of 33 publicly announced clinical holds between January 2020 and December 2022 found that approximately 80% were eventually lifted, after an average of 6.2 months. The most common trigger was an adverse event or patient death. AAV-based gene therapies accounted for 15 of the 33 holds in that period.
The scale of the field amplifies this pattern. Through December 2025, the FDA had approved 48 cell and gene therapies. A 2025 viewpoint in JAMA Neurology placed the current clinical pipeline at more than 2,000 active trials and 37 FDA-approved products, noting that "unexpected, novel, and severe adverse events or death may occur" and that many trials have been paused or halted as a result.
These numbers carry a straightforward implication. Safety events will continue to occur across the gene therapy field. They are an inherent feature of developing therapies that permanently modify a patient's genome with vectors whose long-term behavior is still being characterized. The relevant question for sponsors is whether they will have the communication infrastructure to respond when the next event happens.
That infrastructure, for most programs, does not yet exist.
A specific example that Astellas shared at the recent ASGCT 2026 Annual Meeting illustrates what happens when safety event communication depends on ad hoc coordination rather than pre-built infrastructure. It’s important to examine because of course, this is not an issue that is unique to Astellas.
When Astellas voluntarily paused the ASPIRO trial for X-linked myotubular myopathy in 2021, the program had dosed 24 participants. A patient experiencing a liver-related serious adverse event died, and the FDA subsequently placed the trial on clinical hold. The sponsor had a Medical Monitor committee, a Liver Advisory Panel, and the clinical governance structures expected of a late-stage gene therapy program. What it lacked was a coordinated communication layer reaching every patient, caregiver, site coordinator, and advocacy group with consistent, IRB-reviewed information at the same time.
Each site managed its own patient conversations. Advocacy groups received information through formal and informal channels at different times. Meanwhile, caregivers, many of whom had children with a severe and progressive disease, sought answers from each other.
This is a pattern that gets repeated across programs and companies. At ASGCT, the gene therapy development community acknowledged that the field needs to "engage honestly with where things are still hard," including the gap between clinical promise and the infrastructure required to support it. The communication problem, visible to individual sponsors for years, became part of a broader call to action.
A Clinical Trial Vanguard analysis of post-market safety infrastructure reached a blunt conclusion: the systems designed to protect patients after gene therapy administration remain inadequate. The problem extends beyond individual company preparedness. The field lacks a standard for what gene therapy patient communication infrastructure should look like.
Most pharmaceutical companies approach safety event communication through a reactive framework. And in conventional drug development, this approach can work. If a patient experiences a side effect from a daily oral medication, they can stop taking it. The safety event has a defined boundary, and the communication challenge, while serious, is bounded as well.
Gene therapy changes this calculus entirely. A patient who has received a one-time gene therapy cannot un-receive it. The vector has transduced target cells, and the therapeutic gene is actively expressed. When a safety event occurs, every patient who has been dosed needs to understand what it means for them, specifically and accurately.
Reactive communication frameworks fail here for a concrete reason: they are too slow. IRB-reviewed patient communication materials take weeks to develop, review, and approve. By the time they reach patients, social media and caregiver forums have filled the information vacuum with speculation, incomplete data, and fear.
The FDA's long-term follow-up guidance requires monitoring gene therapy subjects for up to 15 years after administration, depending on vector type. This mandate assumes that sponsors will maintain ongoing contact with patients over that entire period. Most sponsors have no infrastructure to support this. The barriers to long-term follow-up in cell and gene therapy are well documented: providers retire, and patients move, lose contact with trial sites, and disengage from programs that offer no ongoing value.
The gene therapy field has internalized that patient engagement matters for recruitment and retention. It has been slower to recognize that engagement infrastructure serves a second, equally critical function. The same systems that keep patients connected to a program during normal operations become the communication channels through which safety information flows during a crisis.
Without that pre-existing connection, sponsors are building the bridge while trying to cross it.
The programs that will handle safety events well are the ones that invested in patient communication infrastructure before a crisis occurred. This means building persistent, bidirectional communication channels with patients, caregivers, and sites as a standard part of program design, rather than as a crisis response.
A patient who has been receiving regular program updates for 18 months has a fundamentally different relationship with the sponsor than a patient who last heard from the trial site at their most recent study visit. When that infrastructure exists, a safety event becomes a communication challenge with existing tools. When it does not, the same event becomes a trust crisis with no established channel for resolution.
Closing the communication gap between sponsors and patients requires infrastructure that operates continuously, across the full program lifecycle.
The ASGCT 2026 panels on safety event navigation confirmed what the field has been slow to articulate: patient engagement infrastructure is trust infrastructure. The systems that keep patients informed and connected during normal program operations are the same systems that enable credible, timely communication when a safety event occurs.
Gene therapy sponsors face a choice. They can continue building communication responses after safety events emerge, or they can invest in persistent patient communication infrastructure before it is tested. The sponsors who navigate the next gene therapy safety event effectively will be the ones who built that infrastructure in advance, as a permanent component of program design.
Sano works with cell and gene therapy sponsors to build persistent patient engagement infrastructure across the full program lifecycle. Get in touch to learn more.