The Insulin-Only Bionic Pancreas Pivotal Trial

Inclusion Criteria:

   - 1. Clinical diagnosis of T1D for at least one year and using insulin for at least 1
   year 2. Diabetes managed using the same regimen (either pump or MDI, with or without
   CGM) for ≥ 3 months

   3. Age ≥ 6 years old

      - Exception: the initial 5-participant test run will be limited to >18 years old

      4. Current use of a CGM, or if not a CGM user, at least 3 blood glucose meter
      tests daily on average over the last 4 weeks (according to judgment of
      investigator if meter is not available).

      5. Willingness not to start any new non-insulin glucose-lowering agent during the
      course of the trial

      6. For participants <18 years old, living with one or more parent/legal guardian
      knowledgeable about emergency procedures for severe hypoglycemia.

      7. For participants >18 years old who live alone, participant has a relative or
      acquaintance who lives within 30 minutes of participant and is willing to be
      contacted to check on participant if study staff feel that participant may be
      experiencing a medical emergency and can't be reached.

      8. Investigator believes that the participant can safely use the iLet and will
      follow the protocol

      - The investigator will take into account the participant's HbA1c level, compliance
      with current diabetes management, and prior acute diabetic complications. For
      this reason, there is no upper limit on HbA1c specified for eligibility.

      9. If a GLP-1 agonist or pramlintide is being used, participant must be willing
      to discontinue use while the iLet BP system is being used, including the
      randomized trial and extension study.

Exclusion Criteria:

   - Eligibility may be assessed initially in a separate screening protocol or at a
   screening visit in the RCT protocol. To be eligible for all phases of the study, a
   participant must meet all of the following inclusion criteria and none of the
   exclusion criteria:

Exclusion

   1. Unable to provide informed consent (e.g. impaired cognition or judgment)

   2. Unable to safely comply with study procedures and reporting requirements (e.g.
   impairment of vision or dexterity that prevents safe operation of the bionic pancreas,
   impaired memory)

   3. Unable to speak and read English

   • For pediatric participants, both caregivers and participants must be able to speak
   and read English

   4. Plan to change usual diabetes regimen in the next 3 months

      - This would include changing from MDI to pump. pump to MDI, change in insulin
      automation delivery system, starting a CGM if not previously used, changes in
      drug therapy specifically for glucose control except for changes in one insulin
      analog to another.

      - Changes in insulin dose, carb ratio, sensitivity factor and basal rate profile
      are allowed.

   5. Current use of non-FDA approved closed-loop or hybrid closed-loop insulin delivery
   system

   6. Use of Apidra as the pre-study rapid-acting insulin analog and unwilling to switch to
   lispro or aspart for the duration of the study

   7. Known hemoglobinopathy (sickle cell trait is not an exclusion)

   8. Current participation in another diabetes-related clinical trial

   9. History of cystic fibrosis, pancreatitis, or other pancreatic disease, including
   pancreatic tumor or insulinoma, or history of complete pancreatectomy

10. Electrically powered implants (e.g. cochlear implants, neurostimulators) that might be
   susceptible to RF interference

11. Established history of allergy or severe reaction to adhesive or tape that must be
   used in the study

12. Current use of SGLT2 inhibitors or a sulfonylurea drug (use more than 3 months prior
   to enrollment is acceptable)

   • If using GLP1 agonist, pramlintide, or metformin drugs must be on a stable dose for
   3 months prior to enrollment (and as per inclusion criterion #8, must be willing to
   discontinue use of GLP-1 agonist or pramlintide while using the iLet BP system during
   the RCT and the extension phase).

13. Pregnant (positive urine hCG), breast feeding, plan to become pregnant in the next 3
   months, or sexually active without use of contraception

14. For adults >18 years old, most recent (must be within the last 2 years) eGFR <30
   ml/min OR currently in renal failure on dialysis

   • If no eGFR is available for an adult participant during the last 2 years, one must
   be obtained to confirm eligibility

15. Presence of a medical condition or use of a medication that, in the judgment of the
   investigator, clinical protocol chair, or medical monitor, could compromise the
   results of the study or the safety of the participant. Conditions to be considered by
   the investigator may include the following:

      - Alcohol or drug abuse

      - Use of prescription drugs that may dull the sensorium, reduce sensitivity to
      symptoms of hypoglycemia, or hinder decision making during the period of
      participation in the study

      - Coronary artery disease that is not stable with medical management, including
      unstable angina, angina that prevents moderate exercise (e.g. climbing a flight
      of stairs) despite medical management, or within the last 12 months before
      screening a history of myocardial infarction, percutaneous coronary intervention,
      enzymatic lysis of a presumed coronary occlusion, or coronary artery bypass
      grafting

      - Congestive heart failure with New York Heart Association (NYHA) Functional
      Classification III or IV

      - History of TIA or stroke in the last 12 months

      - Untreated or inadequately treated mental illness

      - History of eating disorder within the last 2 years, such as anorexia, bulimia, or
      diabulemia or omission of insulin to manipulate weight

      - History of intentional, inappropriate administration of insulin leading to severe
      hypoglycemia requiring treatment

16. Employed by, or having immediate family members employed by Beta Bionics, or being
   directly involved in conducting the clinical trial, or having a direct supervisor at
   place of employment who is also directly involved in conducting the clinical trial (as
   a study investigator, coordinator, etc.); or having a first-degree relative who is
   directly involved in conducting the clinical trial