After a week with this new insulin, I thought it was worthwhile having a quick review of what I’ve learned and how well it works for me.
As readers will know, after 24 hours, I wasn’t seeing very much in terms of the so-called ultra-rapidness of the insulin that had been displayed in the various trial data that had been put forward. This was using it in a pump, with a hybrid closed loop.
Using as an injection
Taking a step back, I decided to run some tests, injecting it as I would if on MDI. In doing this, it consistently met the target of being ultra-rapid. Pretty much like clockwork, 30 minutes after an injection, glucose levels would start to drop. Really fast. An example is shown below.
This behaviour seemed to work every time, and suggests that when I use it for discreet injections, I see the same effect as those who have participated in the trials.
Using with the pump
With the pump, however, it was a different matter, for me. And I stress the “for me” as this is n=1 and doesn’t mean it will be the same for others. The infusion sets in use throughout were Medtronic MiO Advance Teflon sets.
As I mentioned, after the first 24 hours, I wasn’t seeing the alleged ultra-rapid effect. Instead I was seeing something more akin to massive insulin resistance.
In this first image, you can see a bolus undertaken 15 minutes before eating. If the effects were as when I injected, you’d expect that upwards trend to be interrupted about 30 minutes after bolusing, but nothing. And OpenAPS SMBs appear to be having no effect either.
In this second image, you can see a meal eaten as glucose levels were dropping and then insulin and food given as the levels inflect. Firstly with the amount given early in this image, I’d have expected levelling off earlier than it did. Secondly, a half hour after the second large bolus, I’d expect the levels to at least start coming down, as IOB was significantly in excess of the COB. Instead they remained almost flat as there seemed to be no effect from the insulin. This raises questions for me about the effectiveness of continuous infusion of Treprostinil for me.
The pump study showed that site issues are a thing with Lyumjev. And the patient Information Leaflet also highlights this.
My experience was that my sites with Lyumjev didn’t hurt when I bolused. However, the site itself became quite tender and felt like there was a large bruise. This made it quite painful and sensitive to touch. This was highlighted when I was in bed and rolled into the site, and the pain woke me up.
In addition to this, the bruise sensation took 24 hours to disappear after I had changed sites. The slightly odd thing was that there really wasn’t very much to show for this. Maybe a slight redness, but nothing abnormal from a used site.
It’s worth bearing in mind that my infusion sets are Teflon and the injection was done with a steel needle, so I need to check whether I see the same effects when using a steel infusion set.
Okay, n=1 and all that. Any other data?
Feedback from other early adopters has been varied. All the users I’ve seen feedback from have been using either a pump or an open source closed loop. Bear in mind that this is still a very small sample, n<10.
They fall roughly into three groups:
- Those for whom it worked perfectly
- Those for whom it didn’t work
- Those for whom it worked but they suffered a site reaction and stopped.
Those in category 1 seem to make up about half. It’s worth noting that one of the success stories here stated they use steel cannulas. I don’t know whether this plays a part. Categories 2 & 3 make up the rest, with one person experiencing a major allergic reaction after 18 hours and stopping completely.
What I take away from this is that individuals will not all react the same way, and care should be taken if providing Lyumjev to users on a pump, as they will need to closely observe what’s happening.
Why this variety in outcomes?
It’s a good question. Lyumjev is accelerated by the addition of Treprostinil to Lispro insulin, which in theory causes vasodilation at the injection site. For me with Teflon cannulas, it would appear that it’s causing other issues. Could it be that the concentration of the additive when used for infusion is simply too high for some of us, and as a result there’s a build up at the site causing issues? Would lower concentration work better in pumps?
We probably need to see more observation on this as more people start to use it and we get a better view on how people get on. If you read the patient information leaflet, there’s a statement that says this product is subject to additional surveillance, so I’d encourage any early adopters that see issues to record them with their local regulatory body.
What next for you?
On its own with my current setup, this has clearly not met my expectations. As a result I’ll look at some of the other things that have been done in the WeAreNotWaiting world relating to using Fiasp. Suffice to say that I’ve stopped using it “neat” for now.
Firstly I’ll try the steel cannulas and see if that makes any difference. I found with Fiasp that they helped, so I assume that while they do more physical damage, there’s less bodily reaction to them, which may ameliorate that impact of Lyumjev.
Secondly, I’ll take a look at mixing the Lyumjev with Lispro and see if that makes any difference.
Finally, it’s worth having some in the fridge purely for stand by. Knowing how fast it does work for me when injected, there may be times where that will come in helpful.
But in total, it has turned out to be somewhat of a conundrum, and not quite what I was expecting. Let’s see what happens next!