Review of FiASP insulin and how it compares with other fast insulins

//Review of FiASP insulin and how it compares with other fast insulins

Faster Insulin: The Holy Grail of Type-1 Diabetes

OK, my kids are right.  I’m a geek.
Monty Python movies still crack me up… especially Monty Python and The Holy Grail.  Love that scene at the “bridge of death” where the creepy guard asks questions that must be answered correctly in order to pass, lest you plunge into the bottomless gorge.  Challenging questions like “what is your name, what is your quest, and what is your favorite color.”


In the diabetes world, the answers to get to the desired insulin treasure are a bit intriguing.


What is your name?  “Just call me ‘tired of waiting for this so-called-rapid-insulin to work.’ ”


What is your quest?  “I seek a faster insulin.”


And what is your favorite color?  “Whatever damn color the faster insulin is, that’s my favorite.” 

Well, our quest isn’t quite at an end.  But we’re getting closer.

Here’s my review of FiASP insulin and how it compares with other fast insulins:

Novo Nordisk’s new FiASP insulin (short for Faster insulin Aspart) has hit the market in various parts of the world, and is awaiting FDA clearance here in the US.  The good news is that it IS faster than the rapid insulins we’ve been using for the past 15+ years (aspart, lispro, glulisine – brand names Novolog/Novorapid, Humalog, Apidra).  The bad news is that it is just slightly faster, and still nowhere near as fast-acting as the insulin the pancreas produces.  It’s also not quite as fast as inhaled insulin (Afrezza) or injections of rapid insulin given into muscle.

But it is an improvement.  By adding niacinamide to the formulation, the insulin molecules form monomers (single pieces of insulin) that move through the subcutaneous fat layer faster than before.


How much faster is FiASP as compared to normal insulin?

Its onset of action is about 6 minutes earlier, the peak is 7 minutes earlier, and it works 50% harder during the first 30 minutes compared to traditional aspart.

The result:   Better post-meal patterns with a peak that is approximately 40mg/dl (2.2 mmol/l) lower. 


What about the duration of action?

Sorry, no difference.

It takes just as long to finish working as the rapid insulins that are currently on the market.  Although it starts out faster, FiASP has a long tail of action.  However, when used to correct high blood sugar, you will notice a more rapid decline during the first 30-60 minutes.

Will FiASP be approved for use in insulin pumps?

Yes, but beware:   The “insulin on board” algorithms will be rendered somewhat inaccurate.  Those algorithms are based on the action profile of traditional rapid insulin, so when using FiASP, the pump will over-estimate IOB during the first two to three hours.  It may be necessary to set a slightly-shorter duration of insulin action in order to have the pump calculate IOB correctly (for example, setting 3.5 hours rather than 4.0 hours).


Does dosing need to be changed when converting from rapid-acting to FiASP?

Unit-for-unit, FiASP has the same potency as rapid-acting insulin, so it should be a relatively easy conversion, and one that I would recommend to most people on pumps and multiple injection programs.  However, don’t fall into the trap of thinking “this stuff is faster… I don’t have to take it ahead of time.”  That’s like buying reduced-fat snacks and then eating the entire package because they’re… well… better for you.  Users of FiASP will still need to pay attention to the timing of their bolus insulin.  In order to see the benefits of the faster onset, it will need to be taken at the same time you take your insulin currently.  Taking it later will negate the benefit.  And with slowly-digesting meals/snacks, it will be more important than ever to delay the injection (or use a dual/combo bolus) in order to prevent post-meal hypoglycemia.

Bottom Line:

So at least we’re on the right track.   Much faster insulin is going to be necessary if our “hybrid closed loop” systems are ever going to become full closed-loop systems.  But for now, an almost Holy Grail is better than no grail at all.

By | 2017-06-21T17:41:35+00:00 June 21st, 2017|Thinking Like A Pancreas Blog|7 Comments

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  1. John June 21, 2017 at 8:47 pm - Reply

    Hmmm… Well, I’m not quite as excited about FIASP as I thought I’d be. Sounds like getting highs down quicker is the best part of it. Should lead to more time in range. More trial & error to come! Thanks for posting the review!

  2. Scott June 22, 2017 at 8:12 pm - Reply

    Thanks for the review Gary. Although a little faster action sounds good, I’m sure this insulin will still carry a hefty price. I would be more excited if the rapid acting insulin manufacturers would deliver on better pricing at this point if no new breakthroughs in therapy are emerging. I will be dealing with Medicare very soon and when you hit that donut hole in coverage, it is very scary to make it through to the other side of the donut hole and still be financially solvent!

  3. Tara O'Hara June 23, 2017 at 12:20 am - Reply

    What niacinamide and what kind of long term effects does that have?

  4. Jennie Dyke June 23, 2017 at 10:04 am - Reply

    Thanks Gary!

  5. Fiasp Insulin June 28, 2017 at 7:23 pm - Reply

    […] author of "Think Like a Pancreas" just posted a review of fiasp insulin Review*of FiASP insulin | Integrated Diabetes Services Most reviews I have seen have not said that the dose is double, or half as effective. I wonder if […]

  6. Tim August 9, 2017 at 6:59 am - Reply

    My experience of Fiasp is rather different from what you’ve written above. I (and quite a few others) have found that we can take it immediately prior to eating and experience very minimal post prandial rises in blood glucose, indeed, I have tested in with a fairly boring white bread and jam meal, with an immediate pre-prandial dose, and found no rise in glucose levels.A fair number of people have found that bolusing as you would with normal fast acting insulins results in hypos very soon after eating. As always, your diabetes may very, and not everyone sees the same effects.

    It seems that the faster onset is not the critical factor in the way this insulin works, but rather the larger availability of insulin in the first 30 mins, which seems to have a major effect. If you’d like more information, I’ve written a lot about it here:

    The other thing to note is that the duration is the same as that of Novorapid. Whilst the curve shape is slightly different, i.e. there is less insulin on board between 3 and 6 hours, it’s very much still there, and setting a pump DIA to 3.5 hours will significantly underestimate this factor out at these times.

  7. SB2015 August 20, 2017 at 10:05 am - Reply

    Thanks for the review. I have switched but I am only three weeks in.

    As suggested post meal spikes are smaller and have become blips on meals of less than 30g CHO. For bigger meals it is a lot less predictable.
    It stings when delivered. I tried extending to 15 min but that just prolonged the stinginess.
    Cannula sited need changing more often, now diong on his daily rather than every two days
    I have reduced the timing before I deliver before meals but reading your review I shall still look at these
    It is a lot better when eating out and I need to wait until the food arrives to deliver. It comes down more quickly than before
    As said correction work more quickly.

    I have decided to give it a proper try and do at least three months. The benefits need to outweigh the stinging in delivery.

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