Trending topics: What immunotherapy researchers are reading now

We look at the research catching experts’ attention in this rapidly evolving field.

ResearchGate is a network where 15 million researchers connect and discover research, and where scientific recruitment solutions help scientists build careers. This gives us unique opportunity to see not just what scientists publish and cite, but how they interact with research every step of the way.

This also means that trends we see reflect the make-up of our network. Most of our members conduct research in Europe (34%), North America (28%), and Asia (26%). Our members come from a range of disciplines, but lean towards the life sciences. Medicine and biology are the two biggest disciplines, making up a combined third of our membership.

Looking at highly cited research over the last few years, we noticed that cancer immunotherapy stands out as a topic of interest. And it’s no wonder citations are trending in this field. Immunotherapy, an umbrella term for therapies that harness a patient’s immune system to attack cancer cells, has revolutionized the treatment of certain types of cancer. FDA approval for existing immunotherapy drugs has expanded to treat multiple kinds of cancer, and new types of immunotherapy are still emerging.

To get a sense of trends in this rapidly changing field, we wanted to look not back at what researchers are citing, but forward at what’s to come as best as possible. So we examined what immuno-oncology specialists have been reading on ResearchGate. Specifically, we looked at how many times individual publications were read by researchers in this field.

We hypothesize that examining what researchers are reading offers a real-time glimpse into the topics they think are important, months or even years before they publish about them. That could give reads advantage over metrics like publications or citations, which might lag behind trends. It takes an average of eight months for research to be published once it’s been submitted to a journal in biomedical fields.

For this trend assessment, we focused on the most active researchers in immunotherapy—ResearchGate members who’ve published at least four immuno-oncology papers since 2016. The following analysis looks at the 100 recent publications read most by this group in the last six months.

PD-1/PD-L1 is dominating immuno-oncology research consumption

Checkpoint inhibitors, in particular those targeting PD-1 and PD-L1, are clearly dominating what immunotherapy researchers are reading. PD-1 is a checkpoint protein that prevents T cells from attacking other cells in the body. It works when paired with PD-L1, a protein abundant in some cancer cells. Some of the most successful checkpoint inhibiting drugs block either PD-1 or PD-L1 to keep cancer cells from using this mechanism to evade an immune attack. A full third of the publications on our list are about checkpoint blockades. That’s significantly more than the next most popular immunotherapy type, oncolytic viruses, which feature in only six studies. A vast majority of these—26 publications in total—look specifically at PD-1 or PD-L1 inhibitors, either exclusively or in combination with other therapies.

“PD-1/PD-L1 immune checkpoint blockade has proven to offer patients better outcomes, while the approved use of these antibodies is constantly being expanded to more cancer types,” explained Karolinska Institute’s Ioannis Zerdes, author of a PD-L1 regulation review that appears on the most-read list.

A stand-out trend within checkpoint blockade research is an interest in biomarkers. "The biggest trend in immuno-oncology now is finding biomarkers that can be used to identify which cancers are more susceptible to certain immunotherapeutic agents and which patients are more likely to benefit from receiving them," said Johns Hopkins University's Michael Lim and Alice Hung, whose checkpoint blockade study topped the most read list.  About a third of the checkpoint blockade research on our list pertains to immunotherapy biomarkers.


Much of the research targets melanoma and brain tumors

Among the studies looking at a specific type of cancer (just over half of the list), there is a clear focus on melanoma. “Melanoma is the cancer that responds most robustly to immunotherapy, which is likely why it’s so heavily represented here,” said Ashani Weeraratna of the Wistar Institute’s Melanoma Research Center. Weeraratna supervised the second most popular study on our list, which finds that older melanoma patients respond better to anti-PD1 therapies than younger ones.

After melanoma, brain cancers also feature prominently, in particular glioblastoma. “Malignant brain cancer is lethal, with very little progress being made over the past 40 years. In children, it has become the biggest killer. There is a desperate need to develop novel therapies,” explains Maria Castro of the University of Michigan. Castro’s publication examining immunotherapy’s potential to treat glioma has also been popular among immuno-oncology researchers this year. The therapy it discusses is now being tested in a Phase 1 clinical trial.


These institutions are producing the most-read research

In addition to what immuno-oncology researchers are reading, we also looked at who they’re reading. Of the authors contributing to the 100 publications on our list, 34 are affiliated with the University of Texas’s MD Anderson Cancer Center, making it the most represented institution. MD Anderson is widely recognized as a leader in cancer treatment. The German Cancer Research Center ranked second, with 10 authors whose publications appear on the list.  Also in the top five are the Wistar Institute, National Cancer Institute, and Johns Hopkins Medicine.