Tandem Control-IQ+

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. The 2IQP randomized controlled trial (NCT05785832, NEJM 2025) enrolled 319 insulin-treated adults with type 2 diabetes (2:1 AID vs. control continuing usual insulin with CGM) for 13 weeks.⁵ HbA1c fell from 8.2% to 7.3% with Control-IQ+ (−0.9 points) versus −0.3 points with usual insulin therapy plus CGM (adjusted difference −0.6, 95% CI −0.8 to −0.4).⁵ Time in range rose from 48% to 64%; the adjusted difference versus control was 14 percentage points (about 3.4 hours/day).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 On 27 April 2026 the FDA also cleared Control-IQ+ for use during pregnancy complicated by type 1 diabetes — the first automated insulin delivery system cleared for pregnancy in the US (a US first, not a world first: in Europe the CamAPS FX algorithm has been licensed in pregnancy for years).¹¹ It is available across the US, UK, EU, Canada and Australia through durable-medical-equipment channels.¹

Europe: pregnancy and type 2, added June 2026. On 5 June 2026 Tandem announced that its Control-IQ+ systems — both the t:slim X2 and the Tandem Mobi — had received a CE mark expansion in Europe covering adults with type 2 diabetes and people with type 1 diabetes during pregnancy, so the pregnancy indication now exists on both sides of the Atlantic.¹²¹³ This is a regulatory expansion, not new evidence: the pregnancy indication rests on the CIRCUIT randomized trial, published in JAMA in October 2025, in which people using Control-IQ spent 12.6 percentage points more time in the tighter pregnancy target range of 63–140 mg/dL (3.5–7.8 mmol/L) — about three extra hours a day — from 16 to 34 weeks of gestation, compared with standard therapy.¹² Because that is a pregnancy-specific target, it is not comparable to the usual 70–180 mg/dL (3.9–10.0 mmol/L) time-in-range figures and does not change this item's time-in-range score. The European type 2 indication rests on the separate 2IQP trial and says nothing about type 1 outcomes.¹²⁵ The t:slim X2 is already sold in several European countries; Tandem says the Mobi should begin launching in select European markets in the second half of 2026 — company guidance, not a confirmed launch.¹²

What's coming. Cost-effectiveness modeling in US type 2 diabetes put Control-IQ+ at about $59,400 per quality-adjusted life-year vs. injections plus CGM, which the authors present as supporting broader payer coverage.¹⁴ 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