Two Minnesota teens with type 1 diabetes are some of the first patients in the nation to start using Medtronic's new insulin pump, a first-of-its-kind machine that can predict when a person will have a diabetic emergency and automatically adjust insulin levels to prevent it.

Allison Scholl, 16, of Edina, and Eleanor Hedlund, 17, of Minneapolis, recently received their new Medtronic MiniMed 670G insulin pumps after using a similar but less-advanced Medtronic pump known as the 630G. Their new 670G units were officially activated on Wednesday in a manual mode, but both teens said they were eager to switch the devices into "auto mode" next week.

"I'm a pretty avid endurance athlete. And it's obviously pretty hard to try and control blood sugar when you are constantly working out or being active," Hedlund said Wednesday after receiving training on how to use the device at Park Nicollet's International Diabetes Center in St. Louis Park. "I'm hoping that it will make me able to train more, or not have to drop out of practice. ... Hard workouts are hard to do when your blood sugar is out of whack."

Scholl, meanwhile, was a longtime user of a different company's insulin pump. She said she switched brands last fall after Medtronic announced a "Priority Access" program that allowed people who purchase a 630G system to be "first in line" when the newer 670G is available commercially, which happened this week.

Medtronic is hoping other type 1 diabetics will follow Scholl's lead and get in line for the 670G.

Company CEO Omar Ishrak said in an earnings call with investors in February that Medtronic diabetes-device sales may slow during the quarter ending in April, as patients postponed purchases in anticipation of the 670G. But Ishrak also reiterated that Medtronic's diabetes business is expected to deliver "double-digit growth" during the fiscal year that begins in May. In the three months ended Jan. 27, Medtronic's diabetes revenue grew 6 percent to $501 million.

Type 1 diabetics have many different insulin pumps to choose from on the U.S. market, but the 670G is the only one with software that can automatically read a person's blood-glucose level, make a prediction about whether it's going to go too high or too low, and then automatically adjust the insulin dose.

Typically, users start in manual mode while learning how to use the device, and then switch to fully automatic mode a week later. In automatic mode, the patient still must tell the device when they plan to eat, and manually calibrate the sensor on a regular basis with a finger-stick. But the device automatically adjusts and delivers the so-called "basal" insulin — the small, baseline level of insulin that is delivered continuously during the day and at night.

"With the sensor looking at the glucose values every five minutes, it will do a better job of modifying the insulin delivery than we have done with our manual settings and our clinical recommendations," said Dr. Amy Criego, a pediatric endocrinologist with Park Nicollet Health Services and one of the researchers in Medtronic's clinical trial for the 670G. "As much as we don't want to admit it, it's smarter than we are."

Type 1 diabetes (formerly known as juvenile-onset diabetes) is the more severe form of the disease. T1D is an autoimmune disorder in which the body attacks cells in the pancreas that make insulin needed to extract energy from food. It's different from type 2 diabetes, in which the body makes insulin but then doesn't use it correctly.

Though the engineering challenge of designing the 670G may be over, Medtronic's new hurdle is manufacturing the device in large enough quantity and then smoothly rolling it out to the market. That challenge was made more complicated last fall, when the FDA approved the 670G on an expedited schedule.

"Back in August we received approval from the FDA for the 630G product. Literally less than a month later, we received approval for the 670G product, which was far faster than what we had anticipated," Medtronic Diabetes Group President Hooman Hakami said in the Feb. 21 earnings call. "So literally in less than a month, we had two products approved right on top of each other."

Soon after, Medtronic announced its Priority Access program.

Under the program, which will be enrolling patients until April 28, patients can purchase a 630G device and get quicker access to the 670G device when it's available more widely. Many insurance plans will cover some or all of the cost of the 630G for type 1 diabetes, as long as the patient's existing device isn't still under warranty.

Under the Priority Access program, a patient can get a 670G for $799. That price can be reduced to $299 if the patient sends back their 630G pump and transmitter, and it can be reduced to $0 if the patient participates in an "approved system access program," according to the Medtronic diabetes website.

In the clinical trial that led to the 670G's approval, patients with type 1 diabetes had no episodes of severe hypoglycemia or diabetic ketoacidosis over three months. Unsupervised patients in the study stayed within their desired range for blood glucose 73.4 percent of the time while using the pump, vs. 67.8 percent of the time with a less-automated pump. The benefit was more pronounced at night, when 670G users were in-range 76.4 percent of the time.

The FDA has only approved the device for type 1 diabetics who are at least 14 years old. The agency says risks associated with the device include hypoglycemia, hyperglycemia, and skin irritation. The device is considered unsafe for children 6 or younger, and for people who need less than eight units of insulin per day.