According to a story from Reuters, the cancer drug developer Loxo Oncology recently released the latest results from the trial testing its investigational therapy LOXO-292. Preliminary results released about a month ago were mostly positive, but the latest data shows even further improvement in performance from LOXO-292. This treatment specifically targets RET mutations, which are implicated in a number of rare cancers such as pancreatic cancer and thyroid cancer.
Loxo Oncology’s preliminary data was largely favorable, as LOXO-292 was able to shrink tumors in 69 percent of patients with advanced cancer that was linked to RET mutations regardless of its origins, and was effective against lung, thyroid, and pancreatic cancers. In the latest data release, which involved a larger number of patients and a longer duration of treatment, this figure rose to 77 percent.
It must be noted that this figure was achieved in patients who had a specific RET mutation which caused the RET gene to fuse with another, which facilitates cancer growth. The drug was also tested against medullary thyroid cancer, which had a different type of RET mutation. Against this type, the success rate was 45 percent.
Dr. Alexander Drilon, the lead investigator of the study, found the results to be “pretty impressive.” There are currently no approved cancer drugs that target RET mutations. The favorable test results come in the wake of the potential of Loxo’s other experimental cancer drug called larotrectinib. This drug targets another genetic mutation linked to the TRK gene, and was effective against multiple types of cancer. It could potentially be approved by the FDA before long.
Loxo’s success in developing treatments that target the genetic pathways that certain cancers exploit has highlighted the utility of genomic testing of tumors in order to determine which genes are involved in order to optimize the effectiveness of treatment.
The role of RET genes in cancer is still fairly small. The fusion mutation appears in about two percent of lung cancer cases, ten to twenty percent of papillary thyroid cancer cases, and some percentage of other cancers, including pancreatic cancer occasionally.
Hopefully, LOXO-292 will gain approval so that cancer patients with these rare mutations can get access to effective treatment.
