The Sequel Med Tech Twiist with Tidepool Loop. Where did it come from, and what is it?

With the recent announcement of the Twiist Insulin pump and AID with Tidepool Loop, a lot of people were left scratching their heads.

Where had this device come from? It appeared seemingly out of nowhere. And yet, I suspect that it’s not quite such a medical newcomer, indeed, I strongly suspect that the device itself is very familiar to a very specific set of users, and it perhaps should come as no surprise that it has then resulted in use for insulin delivery.

But let’s start with the hints…

Diabetes Mine Innovation Days – Fall 2024

Why this event? The guest speaker. Dean Kamen of DEKA research. A key message I took away from his presentation at the event was that they try to innovate by reuse of technology. A classic example being the Segway, into the iBot mobility wheelchair, into FedEx delivery automatons.

Dean Kamen slide on innovation by reuse

At the event he also talked about taking the Freestyle drinks dispenser and using the technology to build IV fluid dispensers for use in hospital.

Finally, Dean was the first person to build insulin pumps, and hinted that he was getting back in the game, and it was not very big…

Noting that Sequel seems to be, similar to many other names, either a DEKA spin out, or one that uses their technology, I decided that it’s time to see what DEKA make that might fit the “Insulin Pump” mould. I didn’t have to look far.


Why are we discussing a different drug, all be it one that’s currently very tightly linked to Diabetes? It’s the active ingredient in Lyumjev.

It is also administered for pulmonary hypertension, and has historically used an insulin pump to do this, until dedicated pumps appeared.

One of the dedicated pumps is called Remunity, and is made by DEKA, for the delivery of Remodulin. A preparation of Treprostinil.

Why do we care? Well if you can use insulin pumps to deliver Remodulin, why not the other way around?

What is the Remunity pump?

Let’s start with the way it looks. It’s remarkably similar to the Twiist.

Compare these two images:

Remunity Pump
Twiist Pump

The top one isn’t shown with the cannula attached, but they seem to be identical.

In terms of size, the Remunity, and therefore I assume the Twiist, is 2″ in Diameter.

Remunity size

So let’s check the user manual for the Remunity pump.

It delivers Treprostinil in microlitres. There are 1000 microlitres per ml, and 100iu (in general) per ml, so one iU is 10 microlitres. It’s not, therefore, that hard, to envisage a pretty simple delivery conversion between iu and microlitres.

Given it already delivers a critical drug, it already has FDA approval as a medical device, with occlusion detection, volume and flow measurement, all of which are critical in an insulin pump. This would make further approvals a lot easier.

And what of the pump itself?

Some details from the Remunity manual

The manual can be found here.

The Remunity pump, when used with Treprostinil, has a couple.of really interesting characteristics. It takes both manufacturer cartridges and refillable ones.

I don’t know whether MedTech have managed to get anyone to agree to manufacture cartridges, but even if not, that’s not really a problem.

The cassettes for Remunity use Luer Locks. The image for the Twiist appears to show this as part of its make up.

The luer lock connectors  appear to be part of the cassette in the standard Remunity pump. I assume that there will either be a Luer Lock or a proprietary connector in the Twiist that works in the same way.

Remunity cassette/reservoir connection

This works with multiple Luer Lock linked infusion sets at the moment. Again, it remains to be seen if Med Tech will be able to license these for use with the Twiist, or whether they’ll have to seek their own sets.

Remunity infusion set choice

In addition, the pump has rechargable batteries that doesn’t require you to attach the pump to a charging cable, but can be swapped independently. I hope this is carried through to the Twiist.

Remunity pump batteries

And where does the name “Twiist” come from. I suspect it’s from the way the connection between the cassette and pump body is locked. With a Twist…

Twisting the Remunity to lock the cassette and pump body together

It apparently also comes with either a belt clip or can be put in your pocket.

And what about remote control?

The Remunity was already designed to use a handset. It’s not the biggest step to provide the protocol to Tidepool for Loop to communicate with it.

And of course this also gives the US another phone based system, after the Tandem Mobi with control-IQ.

Tidepool Loop

Unfortunately, if you use an Android phone, it’s still an issue, as both Mobi and Loop only run on Apple devices at the moment.

Is this all speculation?

To some extent yes. Treprostinil was delivered using insulin pumps long before it had bespoke pumps. So it makes sense that it might work the other way.

The Remunity pump has all the characteristics relating to accuracy, control and inbuilt monitoring that an insulin pump needs.

I look forward to seeing this in the flesh working with Tidepool Loop. It looks like a compact pump with some smart features and I hope they are able to get it into production and available for use, sooner rather than later.


    • That’s really a question for Tandem. Do they think that they’d sell more pumps by opening up to Tidepool Loop as well as ControlIQ?

      Would having two, very similar, systems, working with their platform help them? Or are they focussed elsewhere on the AID front?

  1. I found this page via Google when trying to find more information about the Twiist insulin pump (specifically, when it’d be out). I love your analysis and agree completely with the re-use of existing technology (something Dean Kamen is known for). Also, the Remunity pump was announced with no other than Dean Kamen in 2021 when Remnunity came out, so it’s just a new application (albeit, a surprise to the type 1 diabetes community). For the product to be successful, it’s going to need great marketing and insurance approval – even if it’s the best tech, it may not sell itself if coverage isn’t there. I would be super-excited if Dean Kamen makes this more of an open-API, enough for integration into smart watches and the like. Hopefully good cybersecurity around the wireless function (as there’s sure to be someone who wants to make a big news item by demonstrating something harmful). I really hope they make progress and make it profitable. Considering I’m seeking a closed-loop system, and fearful of picking a less-than-optimal solution that I’d be stuck with (due to insurance) for 3-4 years, I’m going to try to hold out for Twiist. It would be exciting to be part of that project and I hope they have a passionate team to deliver.

    Sorry for the ramble — other than I wanted to post to say thanks for the analysis and your passion to diabetes tech. Looking forward to digesting more articles here since this is my area of special interest. 🙂

  2. Thanks for this report, Tim. You will see it in the flesh if you can join us for the Summer 2024 DiabetesMine #DData ExChange event on June 21 in Orlando!

    • Wow, I’m star-struck seeing you post here (I was a fan of your blog early in my diagnosis days; I think we were dx’ed around the same time, and I liked your writing style). Thanks for your efforts in pushing technology in the diabetes world. It’s so frustrating that companies like Abbott have locked down the device data into an encrypted database that runs on phones, and lack innovation or making a good software product. If they offered an open API to access live data (rather than put it behind a CAPTCHA request that adds extra delay in data retrieval), folks could innovate more: write software to push to any watch attached to a phone; write their own insulin dosing calculators using live data; write their own analysis and reporting. Abbott is holding all the cards. I hope someone from their industry would just listen to the needs of the diabetes community. (On the other hand, I think I’ve heard Dexcom with a far more open attitude; if true, I’m making a switch and will insist everyone I know who can afford to switch to do so, until Abbott opens their API and stops encrypting their — wait — it’s my personal own — glucose data.

  3. Hi Jason,
    Thank you so much for your kind words about my work!

    There has been frustration all around that the established medtech companies aren’t doing enough on the open data front. Luckily, lots of good folks are out there fighting the good fight.

  4. I am holding out for the Twist, I am on the Tandem x2 and hope to switch out sometime this fall into a new system. I would like to try out Twist as a research study to see how it works with an older adult with 52 years with type 1.

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