It is in clinical trials that are looking at whether it can prevent the return of ovarian, endometrial, and breast cancers.
In June 2016, the U.S. Food and Drug Administration granted two orphan drug designations to GALE-301 as an ovarian cancer treatment. One of the designations was for GALE-301 as a stand-alone therapy and the other for a combination of GALE-301 and GALE-302.
How GALE-301 works
GALE-301 is a combination of a peptide, or short fragment of a protein, and an immune-boosting molecule. The peptide, E39, is derived from the folate binding protein, or FBP. The immune-boosting molecule is granulocyte macrophage-colony stimulating factor, or GM-CSF.
Various cancers, including ovarian, endometrial, and breast cancer, produce excessive amounts of FBP, which makes FBP a good substance to build a vaccine around. GM-CSF is a cell signaling molecule that triggers the production of immune cells, including macrophages and dendritic cells.
The peptide part of GALE-301 functions as a vaccine since it has the ability to prompt immune T-cells known as cytotoxic T lymphocytes to attack cancer cells that generate FBP.
GALE-301 in clinical trials
Galena has completed two early-stage clinical trials of FBP peptides as treatments for ovarian, endometrial, and breast cancers.
A Phase 1/2a trial (NCT01580696) evaluated GALE-301’s ability to prevent the return of ovarian or endometrial cancer in patients who had received standard treatment.
The Phase 1 stage of the trial dealt with dose escalation. It compared different doses’ ability to trigger immune responses in 30 people with either recurrent or non-recurrent endometrial or ovarian cancer who had received chemotherapy. One finding was that a more aggressive disease responds poorly to GALE-301 treatment.
Galena said the Phase 2a stage of the trial compared three doses in a larger population of 51 patients. When researchers saw a limited response to a dose, they increased it. Altogether, patients received six vaccinations — one every 21-28 days.
The Phase 1/2a trial showed that GALE-301 triggered a strong immune response, with responses increasing as doses increased. The highest dose showed promise of being able to prevent cancer from returning. The trial also demonstrated that patients tolerated the vaccine well.
Galena plans a Phase 2b trial in a larger patient base to confirm how GALE-301 works against endometrial and ovarian cancer.
Since E39 revs up the immune system, it poses a risk of immune cells becoming unresponsive to it — a situation known as clonal exhaustion.
So Galena decided to conduct a Phase 1b trial (NCT02019524) to see whether a less potent form of E39, which it calls GALE-302, could trigger an immune response while posing less danger of clonal exhaustion. The participants had received standard treatment for either breast or ovarian cancer and had shown no evidence of their disease returning.
Thirty-five breast cancer patients took part in the study at the University of Texas. They were divided into three groups, with each patient receiving six monthly injections. Those in group A received six GALE-301 inoculations. Those in group B received three GALE-301 inoculations followed by three with GALE-302. Those in group C received three GALE-302 inoculations, followed by three with GALE-301.
Preliminary results showed that administering GALE-301 first and then GALE-302 triggered a better immune response. Patients tolerated both treatments well, researchers said.
The trial is continuing. Researchers hope to determine an optimal vaccination strategy — one that will both trigger and maintain an immune response that prevents cancer from returning.
Immuno-Oncology News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.