Luke Gill, Head of Oncology, and Will Chen, Global Head of Regulatory Affairs, Emerald Clinical presented as a webinar, alongside Dr. Rokuya Nochi of EPS Japan, September 2026.
Most sponsors are comfortable with the idea of running a trial in the US or Europe. The familiar regulatory pathways, long-established site networks, deep KOL relationships and the strategic tradeoffs are well understood. As a result, the decision is considered ‘routine’ and relatively low-risk. Conversely, the decision to bring Asia-Pacific into an oncology development plan is often made too late or made reactively once enrollment in Western sites has already stalled. It is still often treated as an afterthought bolted onto a protocol built for the US and Europe, a situation which adds cost and complexity without delivering the acceleration it is capable of. In the current drug development paradigm, this is an outdated mindset. Getting the APAC decision right helps sponsors compress oncology clinical development timelines by as much as 12-18 months.
The difference between those two outcomes comes down to when, not if, APAC enters the conversation.
The data shows a six-plus month acceleration
Sponsors evaluating early phase oncology trials often work from a single enrollment forecast, an average built from assumed site activation speeds, patient availability, and screen failure rates. Averages like these hide the variation that heavily influences whether a program hits its timeline. And it is not insignificant. This type of variation can lead to delays of 6-9 months without sponsors realizing it until it is too late. Modeling enrollment as a distribution rather than a point estimate, using Monte Carlo simulation across thousands of iterations, gives sponsors a probability of meeting a specific deadline rather than a hopeful target date on a slide.
Running that model against a Phase II to Phase III antibody drug conjugate program targeting 350 evaluable patients exposes the tremendous difference between the different strategies:
- A Western-only baseline of the US and Europe does not cross an 80 percent confidence threshold for completing enrollment until 21 months.
- Adding Australia alone moves the needle modestly.
- Adding China and Japan alongside the US and Europe, a dual engine strategy, reaches 50 percent probability of completion at 12 months and crosses that same 80 percent threshold a full six months earlier, at 15 months.
The data makes a clear and powerful argument for incorporating APAC early, rooted in statistical probabilities.
The path to integrating APAC into your studies from the beginning
However, the gains only materialize when APAC is designed into the protocol from the start rather than added in response to slow Western enrollment. Under the ICH E17 framework for multi-regional clinical trials, a protocol authored for global regulatory acceptance from day one lets sponsors run independent regulatory strategies in each region so that a delay in one market never cascades into the whole program. That means optimizing dose selection early, in line with the Project Optimus approach to characterizing dose through escalation and expansion cohorts, and building APAC feasibility into that same foundational work rather than layering it on once a program is already underway.
China illustrates how far the regulatory environment has moved to support this kind of integration. Since joining the ICH in 2017, China has adopted the large majority of ICH guidelines, and the NMPA now accepts foreign clinical data under defined conditions. Standard IND review runs 60 working days, and a newer accelerated pathway available to programs developing simultaneously across regions can bring that down to 30. For sponsors, this generally does not mean additional research or development work. But it does mean additional regional documentation, such as batch records and test method SOPs for biological products, translated and filed alongside the same global CMC and nonclinical package already built for other markets.
Japan as a gateway
Japan is frequently misunderstood as a market sponsors can address later. Japan is the world’s fourth largest pharmaceutical market, and its universal health insurance system typically moves a product from regulatory approval to reimbursement in about two months, compared with roughly 20 months in many European countries. Programs designated under Japan’s Sakigake system can move through review and approval in approximately six months. As Dr. Rokoyo Noshi of EPS Japan explains, PMDA has also become an increasingly flexible partner: where existing PK, clinical, and nonclinical data show no clinically meaningful ethnic differences, sponsors may be able to skip a dedicated Japanese Phase I study and include Japan directly in a global MRCT, provided that case is built through early engagement with PMDA rather than assumed.
Japan’s oncology landscape also has its own scientific logic. Dr. Noshi’s data showed a significantly higher incidence of lung, pancreatic, liver, and gastric cancers compared with Europe and the US, and antibody drug conjugate programs in Japan have grown roughly thirtyfold since 2004. Sponsors who wait until a pivotal Phase III program to consider Japan are working against both the regulatory timeline and the epidemiology.
As Dr. Noshi notes, involving Japan mid-Phase II is not too late, so long as there is enough runway after site activation for a meaningful number of Japanese patients to contribute to enrollment. The mistake sponsors make most often is treating Japan site selection as an administrative task decided by reputation, rather than a strategic decision built on patient availability and localized protocol design from the outset.
What this means for sponsors
To be clear, not every oncology program needs to include every region. The decision to include APAC, and which combination of Australia, China, and Japan makes sense for a given asset, deserves the same rigor sponsors already apply to US and European site strategy. The key point is that the decision must be made early enough to shape the protocol rather than rescue it. For sponsors planning first-in-human oncology studies or building toward an accelerated oncology proof of concept, that decision increasingly determines whether a program reaches its go or no-go milestone on schedule or six months behind. An oncology CRO like Emerald Clinical works with sponsors on exactly this kind of scenario planning, including the gap analysis and enrollment modeling described here, and we welcome the conversation.