Customised Enteric Capsules Show Promising Results For Oral Delivery Of GLP-1 RA

[0:00:23] So yeah, today we are going to talk about customer enteric capsules to deliver to orally deliver. GLP-1 receptor agonists. 

[0:00:47] So I cannot go to the next slide. 

[0:01:11] Thank you so GLP- 1 receptor agonists. As you may all know, there are a class of therapeutic molecules using the treatment of diabetes and obesity, they are generally administered through injection because of their inherent properties, preventing their oral bioavailability, and this results generally in poor patient compliance, especially in people suffering from needle phobia.  

[0:01:35] So it would be really interesting for these patients to have an oral solution, but because of their inherent properties, GLP-1 results in a very low oral bioavailability.  

[0:01:59] This is due to the high molecular weight preventing their permeation and their permeation across the mucus layer and their permeation across the epithelial barrier, and they're also highly sensitive to the enzymatic degradation and also to the acidic degradation in the stomach. 

[0:02:22] So there are numerous strategies being evaluated to overcome these barriers. One of the most promising one is the use of lipid based combination and also permeation enhancer. So lipid based permeation, lipid-based formulation are really interesting because of the lipophilic environment that they offer to the encapsulated peptides. Because this lipophilic environment prevents the penetration of enzymes and offer good protection to the encapsulated peptides.  

[0:02:46] These types of formulation needs to have some prerequisites to work. If you have listened to Andreas yesterday, you may already know the formed particle size of the lipid based formulation should be small enough to have a good penetration across the mucus and the epithelial barrier, they should be neutrally charged or negatively charged to penetrate across the mucus layer.  

[0:03:10] And of course, the peptide that you want to encapsulate needs to be slightly lipophilic to have a good encapsulation loading in the formulation for that, we can use hydrophobic ion pairing to slightly change the lipophilicity of the peptide. This is a nice strategy because it's also very it's a scalable and easy to implement. 

[0:03:34]  To boost the permeation of the peptides. You can also add permeation enhancers to the formulation. The interest of lipid-based formulation is that some components of this formulation of themselves, permeation enhancers, such as medium chain fatty acids and yeah, and to avoid all the gastric environment, it is good to have an enteric dosage form to maximize the absorption in the intestine of your peptide.  

[0:03:58] So here is a case study we have performed in the lab with the combination of these three aspects, so lipid based formulation, permeation enhancer and enteric dosage form.  

[0:04:22] So we have focused on model GLP-1 receptor agonist, which is exenatide, well known peptide model, and we have form hydrophobic ion pair to increase its lipophilicity to be able to load it in a lipid-based formulation. So, when you form a nitrophobic ion pair, you ionize your peptide in acidic condition to form cationic charge, and you incubate it with the counter ion.  

[0:04:45] So here in our case study, we have used sodium docusate and sodium laurysulfate. And here you can see on the left hand side the results. So, the idea is to maximise the yield of this hydrophobic ion pair formation, and to maximize the log p that you obtain with your HIP. So on the results, you can see on the top graph, you have the measurements of the conversion yield into a hydrophobic ion pair.  

[0:05:09] We can see that for both anionic counter ion, we have maximized this HIP formation for the one to four molar ratio, which is normal because we exhibit four cationic charge on the exenatide in hazardous conditions.  

[0:05:33] So, we selected this both HIP one to four ratio, and we measured the log p on these 2  HIPs. And you can see on the bottom graph that On the left side, you have the log p of exenatide, which is minus 3.5 and we have a log p increase to almost neutral log p for the laurysulfate HIP and for the docusate HIP, we have the an increase of about four units to reach about a log p of one. 

[0:05:57]  So we selected this HIP for the next steps of the lipid based formulation development. For that, we measured the solubility. So, our new API is our HIP. We measured the solubility of this HIP in lipids a wide range of lipid excipients to cover the lipid space. You can see that when we don't have this HIP formation, when we measure the solubility of native exenatides, we have almost no dissolution in the lipid excipients.  

[0:06:21] But when we form our exotic document HIP we have solubility. At least. The maximum solubility was measured in Labrafac 60 and in propylene glycol. So, we have used these excipients to test different binary internal mixture. And we end up, ended up with this formulation you can see on the right-hand side with Labrafac MC60, Kolliphor RH40, propylene glycol. 

[0:06:45]  We loaded in the formulation six milligrams per grams exenatide as HIP which correspond to a dose of three milligrams exenatide in size one capsule and 4.1 milligram of exenatide in size zero capsule, we also tested the solubility of sodium cap rate, a well known permeation enhancer in the same excipients.  

[0:07:08] And we in we manage, we managed to load 20 milligrams per gram of sodium cap rate as a solution in the same formulation. And the final solubility of exenatide docusate in this formulation was 7.6 milligram per gram, which is quite high for a peptide in such formulation, but we decided to go for those of six milligrams per gram to have a safe margin. 

[0:07:32] So we wanted to test if we have these protective effects provided by the lipid-based formulation, because this is one of the main objective of such formulation. So, we have co incubated our lipid based formulation with alpha chymotrypsin. 

[0:07:56] You can see the black curve, we have the control. So we have effectively a high degradation of exenatide by alpha chymotrypsin. And when it is loaded in our prototype formulation C1 we can see that we recover in 80% of the peptide at the end of the test after one hour in the presence of the enzyme. 

[0:08:20] So then I said we wanted to develop our strategy was to have lipid based formulation, permeation enhancer and enteric dosage form. So regarding enteric dosage form, now I want to go next slide.  

[0:08:44] Regarding enteric dosage form so we have in our portfolio capsule, gel and protect capsule, which was launched three years ago. It is ready to use bilayer capsule made of HPMC and HPMC-AS so the internal layer is made of HPMCs provide the structural properties of the capsule, and we have an outer layer of HPMC-AS, which is an enteric polymer providing the functionality to the capsule.  

[0:09:08] The overall thickness of this capsule is the same as standard capsule, so you don't have any problems in using them on standard capsule filling equipment. So it's really smart tool for your development. Because you open the capsule, you fill your formulation, you close and it's done.  

[0:09:31] You don't need sealing of the capsule, and it's you are already have an enteric dosage form. So to prove what I'm saying, we have tested in many conditions. So I will only provide here an overview of some of the characterization that we have done. Next slide please. 

[0:09:55] So we tested in company all the solution test the performances of the capsules. You can see here we have used a small molecule, acid sensitive model, which is Esomeprazole Magnesium. We've underfilled the capsule so detrimental condition for the capsules did not bend in or seal the capsule, and we placed them in acidic conditions for two hours.  

[0:10:19] You can see, for the first two hours, we have no release of the API, and as soon as we switch pH, we can see a fast release of the encapsulated API. And you have here a picture of the capsule, where you can see that it's disintegrating really fast as soon as we switch pH, what is interesting to notice is that we recover 100% of the dose, meaning that we didn't degrade the encapsulated API. 

[0:10:43] On the following slide, you can see the results that we obtain in vivo. So we have tested our capsule in human in fasted and fed conditions. So here are only the results for the fasted condition, but we can share later on, if interested the fed condition results, so to evaluate where the if the capsule was actually enteric, and where it disintegrates.  

[0:11:07] So we have combined two methodologies, being MRI localization, so scanning the volunteers every 15 minutes, and we have also encapsulated caffeine to be able to dose in the saliva of the patients when the caffeine is being released from the capsule.  

[0:11:31] So here [no sound for approx. 10 seconds] and what it enabled us to release the contents irregardless of the gastric resident time, we have always an opening of the capsule 45 minutes after gastric emptying. So it enables to, no sorry, to release the contents in the can you go back? It enables to release the contents in the jejunum or the ilium of the of the patients. 

[0:11:54] Yeah, and we observe the same conditions in the Fed conditions where the where, while we have a more drastic para conditions.  

[0:12:18] So back to our GLP-1 case study. We wanted also to check if we are able to protect larger molecules. So we know that we have the protection of small molecules such as Esomeprazole hydrase.  

[0:12:42] We wanted to know if we were able to conserve the activity of larger molecules, such as protein or peptides. So we encapsulated in our capsule pancrea lipase, which is a protein able to hydrolyse triglycerides into fatty acid and monoglycerides.  

[0:13:06] We have to see it in the SHIME model, bio relevant in vitro model, and we have observed we recovered the activity of the encapsulated pancreatine with 60% of butyrate condition at the end of the test.  

[0:13:30] And also, we have the same activity as the reference which is clear. So, with this bunch of results, we know that we have really, we have disintegration of the capsule when the pH switch to pH 6.4 we have in vivo performance of the capsule. We have proven that it's truly enteric and that we have protection of the largest molecules.  

[0:13:54] So, I my talk is entitled, customized capsules. So why customized it is because this bilayer technology, this bilayer manufacturing technology, for end protect capsule, can be adapted to various types of capsules. So indeed, with our Innovaform accelerator, we are able to customize the capsule. We can change the size of the capsule. We can change the design of the capsule. We can change the polymer so the inner layer, the outer layer, to bring functionality to the capsules.  

[0:14:17] And we offer our customer the ability to test this new capsule for proof of concepts, meaning that you don't have to pay for huge developments and thouands of capsules, but you can already test your concepts on a couple of hundreds of capsules. So, and we guarantee that what we develop in the lab with scalable concept. 

[0:14:41] So here are some examples of what we have done. So back to our case study with exenatide. We have developed a lipid based formulation with a permeation and enhancer. But we know that some of these lipid-based compounds, they are not compatible with the HPMC inner layer of our capsule. So I wanted to test, is it possible to have a gelatin based enteric capsule? 

[0:15:05]  So we manufacture this capsule at pilot scale. So indeed, what I was showing here on the right is our pilot scale capsule manufacturing equipment that we have in the lab, so pilot scale is already very large equipment, and on this equipment, we manufacture gelatin-based capsule with the same dissolution tests, we have proven that we have truly enteric capsules. 

[0:15:29]  And when we fill the formulation you can see in the disintegration, we have a compatible formulation in the capsules, no the opening of the capsule in the acidic conditions. 

[0:15:53] Another customized capsule that we have manufactured in the lab was to address this problem. Statement being that when you feel most of permeation enhancer are sodium based, sodium, when you have the hydration of the capsule shell, you can have local solubilization of your sodium-based permeation enhancer, creating an increase in the pH and dissolving the HPMC layer, and then you lose the enteric properties of your capsule. 

[0:16:17] So we wanted to prevent this hydration of the shell. And for that, we incorporated in the capsule shell a hydrophobic agent. And we fill all the capsules with sodium capulate, so well known permeation and answer. And we can see, so here is the standard, the performance of the standard and protected capsule.  

[0:16:40] We can see we are forming holes in some of the tested capsules, but when we use our customized capsule with the hydrophobic agents, we can see on the right side that we have nothing comparable with the capsule looking unaltered by the filling material.  

[0:17:04] Last type of customization that we were able to test in vivo was the changing the HPMC-AS grade. So depending on the AS grade that you're using, you can have different dissolution pH.  

[0:17:28] So our standard printed capsule is based on the H grade dissolving at pH 6.5 but if you want to have opening earlier in the intestine, you would want to test maybe M grade or L grade, dissolving at pH 6 or 5.5 so we tested all this capsule in vivo, and we were actually able to visualize a difference in the opening localization of this capsule. So the standard capsule mostly open in the ileum of the patient.  

[0:17:52] And we can see that when we use the M grades, we have opening mostly in the jejunum of the patients. Finally, when we use the L grades dissolving in pH 5.5 we have very early disintegration of the capsule, and some of the capsule open in the stomach of the volunteers, which is maybe not what we want for an enteric solution. 

[0:18:16] So this is the end of this presentation where we have seen that lipid based formulation are scalable, viable technology to administer overly peptides, and that we have an enteric capsule of the shelf capsule, which demonstrate high performance in vitro and in vivo, and that our lab is able to support our customer development for developing proof of concept capsules, but also formulations to solve their drug delivery changes through capsule innovation. So thank you for listening.