An invention originally conceived by missile defense specialists at Massachusetts Institute of Technology (MIT; Cambridge, Massachusetts) is showing promise as a breast cancer therapy that could help women with large tumors avoid mastectomies.

New data from a 28-patient Phase II study, led by Alan Fenn, PhD, MIT senior staff member and the technology’s inventor, sought to combine the adaptive phased array (APA) technology with chemotherapy to reduce large breast tumors, allowing for lumpectomy rather than mastectomy.

“In patients who received both the APA and chemotherapy, tumors showed 50% more shrinkage than tumors that strictly received chemotherapy,” Fenn told Diagnostics & Imaging Week. “This has a huge potential for breast cancer because breast tumors have a high water content and microwave has the potential to reduce these types of tumors and avoid mastectomies.”

The APA technology, licensed from MIT to Celsion (Columbia, Maryland) was later licensed to Celsion Canada (Toronto).

In the current study, sponsored by Celsion Canada, a two-channel 915 MHz focused microwave APA thermotherapy system (dubbed Microfocus APA-1000 Breast Thermotherapy System) was used. A closed-end plastic catheter is inserted into the primary tumor under ultrasound guidance, and a combination E-field focusing sensor and temperature sensor is inserted in the catheter to focus the microwaves and measure the tumor temperature during thermotherapy. The system works to reduce energy to surrounding healthy tissues, just as an anti-missile system would work to deflect a missile attack.

Fifteen of 28 patients received two cycles of chemotherapy, followed a few hours later by thermotherapy, in which a microwave was focused on the tumor, raising its temperature to 108 F. After the combined treatments, 14 of the patients’ tumors decreased enough for lumpectomy: the volume of the tumor shrank by about 88%, compared with 59% in patients who received chemotherapy alone.

“The objective was to get a lumpectomy,” Fenn said. “The standard of care would normally be for preop chemotherapy to shrink the tumor and it works, but it’s not that effective. So we wanted to add the heat to get more shrinkage. Now we’re ready to run a large study.”

Whether that large study is funded by the Canadian branch of Celsion or not depends on funding. In January 2006, Augustine Cheung, PhD, Celsion’s founder and CSO, resigned and acquired the breast cancer treatment subsidiary, Celsion Canada, for $1.5 million. He committed Celsion Canada to payments of a royalty of up to an additional $18.5 million on future sales of APA-based products.

In an effort to further fund the company, Celsion Canada is now seeking to merge with a holding company, Medifocus (Toronto).

Celsion Canada’s COO, John Mon told D&IW the reverse merger — valued at $7 million — is on temporary hold pending Medifocus’ ability to raise the funds, which he believes will occur in early 2008.

“The intent is to raise enough money to complete the pivotal trial and then fund commercialization,” he said. “Regardless, we anticipate approval from FDA and Health Canada to begin that trial during the first quarter of 2008. If the merger is not complete, the technology will still be developed through Celsion Canada.”

If the merger is approved, both Cheung and Mon will remain at the helm as CEO and COO respectively.

Celsion Canada estimates the cost of the technology would initially be $50,000 with a recurring revenue stream from sales of disposable needle sensors for each treatment costing $1,500.

Previous studies include a 10-patient Phase I trial with 10 patients which showed the technology safely heated breast tumors of up to 8 cm in diameter to treatment temperature. A Phase II dose escalation study, involving 25 patients, established optimum safe heat treatment dose.

The upcoming pivotal trial will likely include more than 200 patients with large breast tumors. Half will receive chemotherapy and the other half will receive the chemotherapy/microwave heat therapy with a primary clinical endpoint designed to establish at least a 40% reduction in tumor size.

Clinical sites would potential include: Princess Margaret Hospital, University Health Network (Toronto), North York General Hospital (Toronto), Harbor Medical Center (Los Angeles), University of Oklahoma Health Sciences Center (Oklahoma City), Comprehensive Breast Center of Coral Springs (Coral Springs, Florida) and St. Joseph’s Hospital (Orange, California).

Fenn said they have not had an opportunity to determine if the therapy impacts overall survival outcomes, but that the technology could eventually be applied to a variety of other cancers. “There are no dangerous side effects to patients,” Fenn said. “The only side effect is skin burn which typically heals.”