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.