NEW YORK — PamGene International is advancing its line of liquid biopsy assays that help guide cancer immunotherapies as it gets ready to jump into the US market.
The company announced in July it had secured CE-IVD marking for its IOpener blood tests for patients with melanoma or non-small cell lung cancer. In an interview, PamGene Managing Director John Groten said the Dutch diagnostic and biomarker services company plans to establish a CLIA laboratory in the US in 2023, possibly by partnering with a lab to conduct US-based pilot studies for its in vitro diagnostic assays.
PamGene is actively looking for such a partner, while it also remains open to possibly licensing its assay technology.
Groten said PamGene likely will launch its IOpener tests in the US market as laboratory-developed tests as PamGene extends its pipeline to include assays for bladder and ovarian cancer. Meanwhile, the company has started developing an assay to predict whether patients with earlier stages of melanoma are likely to respond to neoadjuvant therapy.
PamGene intends to develop the assays as LDTs.
According to Groten, immune checkpoint inhibitor therapies can benefit anywhere from 10 percent to 50 percent of patients, depending on the type of tumor they have. The IOpener assays, he said, can help identify those patients for whom such expensive treatments would be appropriate while also excluding those who wouldn't benefit from the therapies.
The IOpener assays measure protein kinase activity of peripheral mononuclear cells in patients who are candidates for immune checkpoint inhibitors targeting CTLA-4 proteins, PD-1 proteins, or both, with results achievable in one week, PamGene said. The tests measure a patient's chances of disease progression in the 24 weeks after starting immune checkpoint inhibitor treatment and provide oncologists a score predicting patients' likelihood of response.
In a study published in 2020 in the Journal for ImmunoTherapy of Cancer, Groten and his fellow researchers wrote that they found significant differences in the kinase activity of peripheral blood mononuclear cells between cancer patients who responded to immune checkpoint inhibitor therapies and patients who didn't respond to treatment. In particular, the study noted differences in pathways governing T-cell migration, infiltration, and co-stimulation.
The researchers profiled the kinase activity of 160 patients with advanced melanoma or non-small cell lung cancer who were treated with anti-CTLA-4 or anti-PD-1 immune checkpoint inhibitors and found that melanoma patients who responded to anti-CTLA-4 had higher kinase activity that was associated with increased immune system activity, and melanoma or NSCLC patients who responded to anti-PD-1 had activity that reflected the presence of circulating tumor-specific T cells.
PamGene leveraged those findings to develop its IOpener assays. The company boasts its IOpener-Melanoma test delivers 70 percent accuracy in predicting treatment response, with 73 percent positive predictive value and 65 percent negative predictive value, while the IOpener-NSCLC test delivers 72 percent accuracy, with 63 percent positive predictive value and 80 percent negative predictive value.
Groten said IOpener assays measure how patients' immune systems respond to their cancer by looking at the signaling protein kinases within healthy white blood cells. That activity tells the story of the immune response and serves as a set of biomarkers that reflect how likely it is that a patient will benefit from immune checkpoint inhibitory therapy.
The IOpener assays are meant to complement other tissue- or blood-based assays that identify biomarkers of properties within a patient's tumors. Combining the proteomic information of an IOpener assay with, for example, the genomic analysis of a next-generation sequencing assay could help guide clinicians to better treat and manage their patients, Groten said.
Though PamGene is expanding its commercial presence, most of its income comes from its established business of providing protein kinase profiling services to pharmaceutical companies, academic institutions, and research institutes through the firm's PamChip microarrays. Groten previously said its work with partners on drug and test development provided the idea to develop its own diagnostics program.
Pharmaceutical companies use the IOpener technology early in drug development, Groten said, but the company is not developing the tests as companion diagnostics.
While PamGene eyes the US market, it is offering the IOpener tests in Europe, where it is working to convince doctors and insurers there that the assays benefit patients and lower healthcare costs. To that end, PamGene is collaborating with oncologists in Germany, the Netherlands, and Switzerland on implementing the assay into practice, with a goal of integrating IOpener tests into the standard of care.
Groten said the company aims to sell the assays to physicians as tools to fine-tune treatments and improve prognosis, and PamGene has started talks with US-based diagnostics companies about potential sales partnerships. The company is currently working with partners in Europe, including insurance companies, to assess the health and cost effects of the assays. He said the price tag for an IOpener assay will be similar to that of next-generation sequencing assays.