By Dr. Christian Schweiger and Gail Dutton
Rare and orphan diseases are appealing targets for drug developers. This is because such diseases often provide an opportunity to be the first true therapeutic breakthrough, but also because of their special status within the U.S. Food & Drug Administration (FDA) and the European Medicines Agency (EMA), as well as the frequent possibility to apply the research to more common diseases later. Yet, developing therapeutics and diagnostics for rare diseases (conditions that affect fewer than 1 in 2,000 people, using the European Union’s definition[i]) can be more challenging than the common diseases that affect tens of millions of people.
One of the greatest challenges is that rare diseases often are not fully understood. There is a relative dearth of knowledge regarding biological mechanisms and biomarkers for the diseases, clinical phenotyping and translational failures. Published data are scarce. In such an environment, the need for the most up-to-date, relevant, scientific information is of paramount importance.
Yet, much of the information about rare diseases is so new it hasn’t yet appeared in scientific journals. Instead, this research is presented at specialized conferences throughout the world and often is only published as conference abstracts or posters. Many major scientific databases, however, do not index conference abstracts, which makes that data virtually invisible to other scientists.
This, in turn, makes clinical trial design particularly difficult because there is little or no historical experience for trialists to draw upon. Consequently, key elements are designed de novo, which may lead to poor study endpoints, ineffective comparator arms, or other potential failure points[ii].
Having the most recent, most applicable data available, however, mitigates some of the inherent risks associated with clinical trials for rare diseases and enables therapeutic developers to design the most relevant clinical study designs. This sometimes is as straightforward as learning why particular clinical trials failed. Consider systemic sclerosis or systemic scleroderma.
This rare disease affects at most, nearly 340 people per million in Europe and more than 440 per million in the U.S. Searching for “systemic sclerosis” or 18 additional, related terms uncovered 53,625 abstracts in the combined Pharmaspectra and PubMed search, but less than half – only 26,932 – in a PubMed-only search. Scientists designing a clinical trial for systemic sclerosis using only PubMed, had only a portion of the data they needed.
Narrowing the search by adding the new IL-6 monoclonal antibody therapy “tocilizumab” increased specificity, but reduced the abstracts to only 84 using PubMed. The combined Pharmaspectra and PubMed search, however, identified 310 abstracts. Replacing the term “tocilizumab” with “IL-6 inhibitor” identified zero abstracts in PubMed alone. Pharmaspectra, in contrast identified 6 abstracts.
The ramifications from a lack of sufficient data can be significant for any therapeutic area, but the margin can be even more troublesome in rare diseases due to the inherent data limitations. One Phase III clinical trial assessing the efficacy of tocilizumab in the treatment of systemic sclerosis failed on the predefined primary endpoint. Although forced vital capacity, a secondary endpoint, improved, the trial failed to meet its primary endpoint of improving skin fibrosis when compared to placebo.
A conference abstract presented much[i] earlier, in 2018, however, noted that forced vital capacity was the most relevant clinical endpoint in a tocilizumab study for this rare disease. A more complete paper discussing the trial was published in 2020[ii] and, finally, the data regarding interstitial lung disease was published in 2021[iii]. Understanding the criticality of improving forced vital capacity, and selecting that as the primary endpoint, could have led to the trial to succeeding.
Pulmonary arterial hypertension offers another example for a rare disease. It affects fewer than 52 people per million population. A search for the term, looking at the most recent two years, identified 2,197 abstracts using Pub Med alone, but 4,252 abstracts using the combined Pharmaspectra and Pub Med search engine.
Likewise, searching PubMed for “Gaucher Disease,” returned only 327 abstracts published in the past two years. There are many more abstracts available, however. A combined Pharmaspectra and Pub Med search identified 564 abstracts. Undoubtedly, some of those additional 237 abstracts contained valuable data that could affect drug development, patient selection, trial design, or outcomes.
The data returned via searches of PubMed versus Pharmaspectra combined with PubMed are representative for the gamut of rare disease data searches. Even when the initial PubMed returns seem well-populated, drilling down to find specific data may dramatically narrow the field.
Restricting data, though, is a luxury that rare disease scientists generally lack, given the limited body of research. Therefore, it makes sense – especially for scientists working in rare diseases – to seek out all the latest and most relevant abstracts in their fields.
Clearly, when you need highly specific data, you need a search engine that can deliver it soon after the data becomes available. The Pharmaspectra database is continually being updated and is world’s largest data lake of information from scientific conferences and publications. It delivers the greatest breadth and depth of life sciences data from throughout the world, thus ensuring our clients have the most up-to-date scientific data possible.
To learn more about how you can access the world’s largest constantly updated global database of scientific abstracts and articles, contact a member of our team through the Request a demo page.
[i] Khanna D. “Efficacy and Safety of Tocilizumab for the Treatment of Systemic Sclerosis: Results from a Phase 3 Randomized Controlled Trial., Meeting Abstract No. 898, Am Col Rheumatology, https://acrabstracts.org/abstract/efficacy-and-safety-of-tocilizumab-for-the-treatment-of-systemic-sclerosis-results-from-a-phase-3-randomized-controlled-trial/ Oct 21, 2018.
[ii] Khanna D. et al. “Tocilizumab in systemic sclerosis: a randomised, double-blind, placebo-controlled, phase 3 trial,” Lancet Respir Med., 2020 Oct;8(10):963-974. doi: 10.1016/S2213-2600(20)30318-0. https://pubmed.ncbi.nlm.nih.gov/32866440 /Epub Aug 28, 2020.
[iii] Roofeh, D. et al., “Tocilizumab Prevents Progression of Early Systemic Sclerosis-Associated Interstitial Lung Disease,” Arthritis Rheumatol. 2021 Jul;73(7):1301-1310. doi: 10.1002/art.41668. Epub 2021 May 25. https://pubmed.ncbi.nlm.nih.gov/33538094/
[i] European Commission. “EU research on rare diseases,” https://ec.europa.eu/info/research-and-innovation/research-area/health-research-and-innovation/rare-diseases_en Accessed October 25, 2021.
[ii] Goldsmith J., Kempf L., Blumenrath S., “The Challenge of Rare Diseases – From Drug Development to Approval,” Global Forum, https://globalforum.diaglobal.org/issue/april-2018/the-challenge-of-rare-diseases-from-drug-development-to-approval/ accessed October 25, 2021.