Cancer drug development for Japanese patients by Western Pharmaceutical Companies carries two main challenges. First, many new agents still offer incremental benefits over existing therapies or are hampered by acquired drug resistance and, secondly, they reach Japanese patients with an ∼2–3 year delay after their regulatory approvals in the European Union and the United States. This is based on the mechanisms of traditional cancer drug development where new agents are either tested as monotherapies or are placed in the context of moderately effective standards-of-care often based on regulatory considerations rather than science. Furthermore, Western cancer medicines are not formally investigated in Japanese patients until late in their development causing a delay for the additional investigations needed to address potential biologic differences in Japanese patients. Greater benefits and faster access for Japanese patients may be achieved through combined progress in cancer genetics, drug development and regulation. The introduction of precision medicine utilizing biomarker-driven patient selection for molecularly targeted agents has been a first step toward greater patient benefit in defined populations. In addition, new treatment modalities such as immunotherapy have become available to induce greater long-term effects. The next wave of innovation to overcome drug resistance and substantially improve patient outcomes may now require co-development of science-driven drug combinations within and across defined pathways within the cancer and the host. Furthermore, integrated drug development strategies are needed to achieve simultaneous availability of new medicines for Western and Japanese patients. This will require investigation of drug dosing, pharmacokinetics and pharmacodynamics in Western and Japanese patients as part of a global development program, which enables us to understand and address differences in cancer genetics, host genetics as well as disease prevalence. Such programs should be accompanied by earlier and more frequent regulatory interactions as well as Japanese regulations supporting effective execution of global programs and co-development of novel drugs. Overall, close collaboration between all stakeholders on the pharmaceutical, academic and regulatory side is needed to accomplish the goal of bringing greater benefit and faster access of Western-developed anti-cancer drugs to Japanese patients.