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Tandem Control-IQ+

Tandem Diabetes Care

The next-generation Tandem algorithm: it keeps the predictive basal control and automatic correction boluses of Control-IQ but adds extended boluses and temp-basal adjustments during automation, runs on both the t:slim X2 and the miniaturized Tandem Mobi, and is the first hybrid closed-loop system FDA-cleared for type 2 diabetes (ages 18+) as well as type 1 (ages 2+).

Available nowStrong evidencehybrid-closed-looptubedphone-controlOfficial site ↗

The scorecard

Time in range76

Type 1 only: the Control-IQ algorithm achieved 71% time-in-range in the DCLP3 pivotal RCT (up from 61%), and ~70% across a type 1 meta-analysis. The 2IQP trial showing 48%→64% was in type 2 diabetes and is excluded from this score.

Hypo protection78

Predictive basal suspension kept type 1 time-below-range low in DCLP3 (a 0.88-point reduction versus a sensor-augmented pump), with severe hypoglycemia rare.

Automation level68

Hybrid loop with true auto-correction boluses (hourly when glucose is predicted >180 mg/dL); meals are still announced, though Control-IQ+ adds extended boluses and temp-basal control while automation stays on.

Average glucose74

Type 1 HbA1c fell ~0.3 points to roughly 7.1–7.4% in the DCLP3 pivotal RCT versus a sensor-augmented pump; the larger type 2 HbA1c drop is not used to score type 1 performance.

Low variability72

Tighter targets and frequent auto-corrections reduce swings, but large unannounced meals still drive excursions in a hybrid system.

Exercise handling70

Manual Exercise Activity raises the target to 140-160 mg/dL; Control-IQ+ adds temp-basal rates (0-250%) usable during automation for activity, stress, or illness.

Customizability76

Adjustable profiles plus Sleep/Exercise modes, and new-to-Control-IQ+ extended boluses up to 8 hours and temp basals while automation stays on.

Access & cost64

Broadly available through DME channels across the US, UK, EU, Canada and Australia; the type 2 indication and Mobi widen who can obtain it.

Freedom (form factor)58

Runs on the tubed t:slim X2 or the much smaller Tandem Mobi; the Mobi shrinks the form factor toward near-patch size, though tubing remains.

Glycemic criteria are scored on the levels actually achieved in large real-world Type 1 diabetes cohorts — not the headline improvement over a trial's baseline (an improvement that looks bigger when the starting population was doing poorly). Type 2 diabetes trial data is never used to score a Type 1 system; where only improvement data exists, it informs the rationale, not the score. Freedom captures form factor and wearability, so a tubeless system is rewarded for the mobility a tubed one can't match.

The full picture

Control-IQ+ is the next-generation algorithm from Tandem Diabetes Care, building on the widely used Control-IQ. Like its predecessor it is a hybrid closed-loop system: a Tandem pump (the touchscreen t:slim X2 or the much smaller Tandem Mobi) running the algorithm, paired with a Dexcom CGM (G6 or G7).1 The algorithm reads CGM values, predicts glucose ~30 minutes ahead, and adjusts basal insulin every 5 minutes — raising, lowering, or pausing delivery to hold glucose in a 112.5–160 mg/dL (6.3–8.9 mmol/L) target.2 It also gives a true automatic correction bolus, up to once an hour, when glucose is predicted above 180 mg/dL (10.0 mmol/L).2

What's new vs. Control-IQ. Control-IQ+ keeps that core but adds flexibility while automation stays on: extended boluses of up to 8 hours (the old limit was 2), and temporary basal rates from 0% to 250% for short-term needs like exercise, stress, or illness — previously you had to leave automation to do this.34 Tandem also widened the eligible population, accepting weights of 20–440 lb (9–200 kg) and total daily insulin of 5–200 units.34

Pivotal trial outcomes. The biggest expansion is into type 2 diabetes. According to PubMed, the 2IQP randomized controlled trial (NCT05785832, NEJM 2025) enrolled 319 insulin-treated adults with type 2 diabetes (2:1 AID vs. CGM-only control) for 13 weeks.5 HbA1c fell from 8.2% to 7.3% with Control-IQ+ (−0.9 points) versus −0.3 with CGM alone (adjusted difference −0.6, 95% CI −0.8 to −0.4).5 Time in range rose from 48% to 64% (a 14-point gain, ~3.4 hours/day more) while the control group barely moved.5 Hypoglycemia stayed rare — one severe event in the AID group.5 In the original Control-IQ type 1 pivotal trial (DCLP3, NEJM 2019), 168 people aged 14–71 saw time in range rise 11 points and HbA1c drop ~0.3 vs. a sensor-augmented pump.6

Automation level. It is still a hybrid loop — you announce meals. But in the type 2 trial, simplified strategies (preset carb amounts or fixed meal doses) gave HbA1c drops as large as careful carb counting, all without raising hypoglycemia.7 Benefit held across age, baseline HbA1c, C-peptide level, and GLP-1 use.89

Exercise. A manual Exercise Activity mode targets 140–160 mg/dL and stops basal if glucose is predicted ≤80 mg/dL; Sleep Activity targets 112.5–120 mg/dL overnight.2

Ages, indications & access. Control-IQ+ is cleared for type 1 from age 2 and for type 2 in adults 18+ — the first hybrid closed-loop cleared for type 2.110 The FDA cleared the type 2 indication on 25 February 2025, with US launch in March 2025; both groups in the trial used the Dexcom G6.10 It is available across the US, UK, EU, Canada and Australia through durable-medical-equipment channels.1

What's coming. Tandem has since obtained FDA clearance to use Control-IQ+ during pregnancy in type 1 diabetes — a first for a hybrid closed-loop system.11 Cost-effectiveness modeling in US type 2 diabetes put it at about $59,400 per quality-adjusted life-year vs. injections plus CGM, supporting broader payer coverage.12 Tandem continues to push toward the Tandem Mobi (its smallest pump) as the flagship Control-IQ+ platform and toward fuller automation with fewer meal announcements.1

References

  1. Tandem Diabetes Care. Control-IQ+ Technology for Automated Insulin Delivery. tandemdiabetes.com (2025). https://www.tandemdiabetes.com/products/automated-insulin-delivery/control-iq ↩ ↩2 ↩3 ↩4

  2. Aleppo G, et al. An overview of the t:slim X2 and Mobi insulin pumps with Control-IQ technology: patient safety and device efficacy. PMC (2025). https://pmc.ncbi.nlm.nih.gov/articles/PMC13089864/ ↩ ↩2 ↩3

  3. Diabetech. Tandem's Control-IQ Just Got An Upgrade: Here's What You Should Know. diabetech.info (2025). https://www.diabetech.info/p/tandem-s-control-iq-just-got-an-upgrade ↩ ↩2

  4. Tandem Diabetes Care (via Business Wire / FinancialContent). Tandem Diabetes Care Launches New Control-IQ+ Automated Insulin Delivery Technology in the United States. (18 March 2025). https://markets.financialcontent.com/pennwell.hydroworld/article/bizwire-2025-3-18-tandem-diabetes-care-launches-new-control-iq-automated-insulin-delivery-technology-in-the-united-states ↩ ↩2

  5. Kudva YC, Raghinaru D, Lum JW, et al. A Randomized Trial of Automated Insulin Delivery in Type 2 Diabetes. N Engl J Med (2025); 392:1801-1812. PMID 40105270. https://doi.org/10.1056/NEJMoa2415948 ↩ ↩2 ↩3 ↩4

  6. Brown SA, Kovatchev BP, Raghinaru D, et al. Six-Month Randomized, Multicenter Trial of Closed-Loop Control in Type 1 Diabetes. N Engl J Med (2019); 381:1707-1717. PMID 31618560. https://doi.org/10.1056/NEJMoa1907863 ↩

  7. Levy CJ, Kanapka L, Brown SA, et al. Simplified Meal Bolus Strategies with Control-IQ+ Automated Insulin Delivery Are Safe and Effective in Adults with Type 2 Diabetes. Diabetes Technol Ther (2025). PMID 41264341. https://doi.org/10.1177/15209156251395035 ↩

  8. Hirsch IB, Kudva YC, Ahn DT, et al. Adults With Type 2 Diabetes Benefit From Automated Insulin Delivery Irrespective of C-Peptide Level. Diabetes Care (2025); 48:2061-2066. PMID 40953318. https://doi.org/10.2337/dc25-1125 ↩

  9. Graham TE, Raghinaru D, Afreen S, et al. Additive Benefits of Control-IQ+ AID to GLP-1 Receptor Agonist Use in Adults With Type 2 Diabetes. Diabetes Care (2025); 48:2154-2159. PMID 41264828. https://doi.org/10.2337/dc25-1753 ↩

  10. Tandem Diabetes Care. Tandem Diabetes Care Announces FDA Clearance of Control-IQ+ Automated Insulin Delivery Technology for People with Type 2 Diabetes. BioSpace (25 Feb 2025). https://www.biospace.com/press-releases/tandem-diabetes-care-announces-fda-clearance-of-control-iq-automated-insulin-delivery-technology-for-people-with-type-2-diabetes ↩ ↩2

  11. Tandem Diabetes Care. Tandem Diabetes Care's Control-IQ+ Automated Insulin Delivery Technology Now FDA Cleared for Pregnancy in Type 1 Diabetes. BioSpace (2025). https://www.biospace.com/press-releases/tandem-diabetes-cares-control-iq-automated-insulin-delivery-technology-now-fda-cleared-for-pregnancy-in-type-1-diabetes ↩

  12. Al Rawashdh N, Patel BV, Wang SM, et al. Cost-Effectiveness of Control-IQ+ Technology in Insulin-Treated Patients With Type 2 Diabetes in the United States. Diabetes Obes Metab (2026); 28:6280-6290. PMID 42086278. https://doi.org/10.1111/dom.70759 ↩

What's next for this

  • →FDA clearance to use Control-IQ+ during pregnancy in type 1 diabetes (already obtained)
  • →Push toward Tandem Mobi as the flagship Control-IQ+ platform and toward fuller automation with fewer meal announcements