Each year in the US, more than 21,000 women will receive a new diagnosis of ovarian cancer according to the latest estimates from the American Cancer Society, while more than 12,450 women will die from the disease. First-line treatment is based on cytoreductive surgery, often a complete hysterectomy, followed by platinum-based chemotherapy. However, with most patients diagnosed at a late stage, patients often experience platinum resistance with multiple recurrences, and there are currently limited effective treatments in this setting.

Developments and opportunities in 2026

Dr Edward Dow, MD, is a medical oncologist in Boston who now serves as Global Lead for Solid Tumor Research in Caidya’s oncology and hematology department. According to Dr Dow, the ovarian cancer field has seen recent advancements, with two FDA approvals for platinum-resistant ovarian cancer, including pembrolizumab in combination with paclitaxelfor PD-L1-positive patients, and relacorilant with nab-paclitaxel. However, while these are positive advancements, neither are gamechangers.

“Platinum-refractory ovarian cancer has been a real barrier for a long time,” says Dr Dow. “The big breakthrough has been mirvetuximabfor folate receptor alpha (FRα)-positive platinum refractory ovarian cancer. That was significant, but FRα is only expressed in about 25% of patients. And if you look up the guidelines, it’s doctor’s choice for a second agent, meaning there’s really no standard of care.”

For biotechnology innovators, this means there are several opportunities at play, including an urgent need for front-line treatment options that result in fewer relapses and longer progression-free survival. Platinum-refractory patients require additional alternative treatment options, with targeted approaches like antibody drug conjugates (ADCs), immune checkpoint inhibitors, and oncolytic viruses showing potential here.

Another key development in recent years is biomarkers. While ovarian cancer is a widely heterogenous disease, Dr Dow says it has been “late to the game” with genomic profiling and personalized treatment strategies, but this is now progressing. Biomarkers such as BRCA1/2 mutations are now used to define genetic subtypes and appropriate treatment paradigms in the front-line setting, while major breakthroughs in FRα research are now shaping strategies for later lines.

A challenging landscape for today’s trials

Analysis from GlobalData reveals that 29 Phase III studies were launched in ovarian cancer in 2025 – almost double the amount from 2024 and 26% higher than the second-highest year. Moreover, in the first four months of 2026, the number of new ovarian cancer trials is already higher than the total initiated by year-end 2023. There are currently 86 ongoing Phase III trials for ovarian cancer around the world and a further 28 in the planning stage.

Like many other areas of oncology, this means the space is highly competitive, particularly with the race to develop ADCs and targeted therapy combinations. At the same time, protocol complexity is on the rise. Trials often include multiple arms or cohorts for analyzing various combinations, including maintenance cohorts to help isolate the effects of treatments like PARP inhibitors from the initial induction therapy. Moreover, as outcomes expand, trials must now measure biomarkers plus multiple endpoints, meaning more complex monitoring and statistical modelling.

Ovarian cancer is already considered rare, and as patient stratification and precision biomarker strategies take precedence in the field, enrollment is becoming more challenging, potentially requiring larger overall sample sizes to ensure meaningful subgroup analysis. This is where large, multinational studies become essential.

“It really comes down to being able to find the patients,” says Corey Eisenberg, Director of Clinical Development at Caidya. “You have to go where the patients are, and a lot of the time you are not going to find that in one country, so you need to expand out. At the same time, you need to have an eye for commercial considerations, such as where you intend to market the drug. For instance, some countries have certain rules regarding patient data and the percent of patients required to be enrolled in-country.”

As Eisenberg explains, broader patient access requires increasingly global studies, which in turn supports broader commercialization opportunities later down the line. But cross-border studies require careful alignment of site feasibility with the sponsor’s end goals to allow for smart country selection and more effective patient recruitment.

Global ovarian cancer studies – benefits and risks  

Standard of care fragmentation is another major hurdle, says Dr Dow. In low and middle-income countries (LMICs), treatment is usually limited to surgery and chemo – though he notes even paclitaxel access may be inconsistent. Modern maintenance therapies like PARP inhibitors are often unavailable, or unaffordable, in LMICs, and access to genetic testing for BRCA mutations is another dividing line, affecting precision therapy programs.

An additional challenge comes when reviewing the data for pharmacogenomic differences. “We have to be very thoughtful about how we combine data from multiple sites across the globe,” says Dr Dow. He references a key learning from lung cancer research, where EGFR mutations in Japanese women were linked to high rates of interstitial lung disease[i], leading to stringent regulatory oversight from the Japanese PMDA.

Moreover, as competition between sponsors intensifies, a global strategy that comprises traditional overseas locations may not be enough. Increasingly, sponsors may need to “think outside the box” when selecting locations, says Eisenberg.

He adds: “You have to balance the commercial goals with being able to find patients and with navigating the competitive landscape, which means you sometimes have to leave your comfort zone to find the right sites.”

With its rebranded NMPA and regulatory approval timelines that are now comparable to those of the FDA, China represents one such opportunity, as does Latin America and previously overlooked parts of Eastern and Central Europe.

Thinking outside the box could also mean collaborating with community health practices. Taking the time to train these potential sites could become a critical differentiator in trial success, with major benefits for patient referral rates.

Biomarker logistics

Global studies also come with logistical challenges, particularly as biomarkers come to the forefront. Biomarker testing is often inconsistent across different regions and lines of care. Where these tests are not already part of the standard of care, infrastructure gaps are possible, with the availability of standardized, accredited testing facilities delaying or even preventing patient selection.

In some circumstances, it may be possible to ship a patient’s sample to a central lab in another country, though this adds logistical complexity and risks degradation and lengthy turnaround times. In China, however, not only are samples not allowed to leave the country, but certain types are also prohibited, adding further complications to the global picture.

The assays used to run the diagnostic can also be a bottleneck, as these should ideally be standardized across regions. Where a novel biomarker is being used, additional time to develop a new assay – or companion diagnostic – must be built in, and this can easily extend timelines beyond expectations. These challenges are not insurmountable, but they require proper planning and a strong centralized team to mitigate risks.  

“The quality of who you’re contracting with is paramount to any biomarker-driven study,” says Dr Dow. “They need to have knowledgeable boots on the ground – people with the right expertise, who know the landscape, who can contract with these labs and understand how samples are collected in that region and what kind of assays are used.”

The bottom line for ovarian cancer research

In ovarian cancer, clinical trial success is increasingly determined by a sponsor’s ability to navigate a crowded, fast-evolving, and operationally complex environment while remaining several steps ahead of the competition. Global studies are essential, requiring rigorous feasibility planning and expert CROs that can take a complex protocol and an ambitious development plan and turn it into a practical strategy, incorporating innovative thinking and site training to tap into under-utilized referral pathways that can boost enrollment.   

As the logistical challenges increase in modern biomarker-driven ovarian cancer studies, sponsors need CROs with a footprint in the right regions and local expertise where it matters. In this challenging landscape, Caidya’s team of medical, scientific, and clinical development specialists can refine your global strategy and accelerate your journey from feasibility to market, helping you define the future of ovarian cancer treatment.

Clinipace, Inc. is owned, operated, managed, and controlled by dMedClinical Co. Ltd., a privately held company, whose investors include entities located in the People’s Republic of China (PRC), and which may be subject to PRC laws and regulations that differ from those of the United States.

[i] Masatsugu Nakagawa et al. Interstitial lung disease in gefitinib-treated Japanese patients with non-small cell lung cancer – a retrospective analysis: JMTO LC03-02. BMC Res Notes 2, 157 (2009). https://doi.org/10.1186/1756-0500-2-157