Delivery Considerations For Ophthalmic Targets With Sanner's Rob Henson

Rob Henson, Director of Design and Engineering for Sanner US, joins Supplier Horizons host Tom von Gunden to discuss injection devices and other delivery technologies for treating chronic ophthalmic conditions. The topic coverage includes patient safety, device ease-of-use, particulate and endotoxin control, and dose size management in both solid and liquid formulations.

Episode Transcript

Tom von Gunden, Chief Editor, Drug Delivery Leader:

Welcome to another episode of Supplier Horizons. My name is Tom von Gunden, Chief Editor at Drug Delivery Leader and, as always, our host for the series.

Today, I'm pleased to be joined by Rob Henson, who is Director of Design and Engineering at Sanner US, provider of delivery device technologies. And today we'll be focusing on the work that they do there in the injection space, particularly for ophthalmic conditions.

Welcome, Rob.

Rob Henson, Director of Design & Engineering, Sanner US:

Thanks for having me, Tom.

Well, it's my pleasure to have you here. So, let's start.

There may be some folks in the audience who aren't all that familiar with the landscape of what's out there in terms of the ophthalmic target indication space that you and the folks at Sanner look at when you think about delivery device technologies that can reach those targets.

So, provide us with an introductory overview of the kinds of target indications and conditions that are out there that you folks work to reach.

Sure. So, Sanner's primary focus has been on technologies that are intended to treat chronic diseases of the eye, such as age-related macular degeneration, diabetic macular edema, diabetic retinopathy, and glaucoma.

We typically have partnered with various pharmaceutical companies to develop and manufacture the delivery devices that enable administration of the therapy.

Gotcha. Tell us about the range of device technologies, the types of device technologies that you folks work on, often, of course, in collaboration with biopharma companies.

Sure, these can be injector-type technologies, delivering either solid dose or liquid dose forms. It could be an applicator for topical delivery of an eye drop. It really just depends on the nature of the therapy and where that therapy needs to go to treat the disease.

Gotcha. So, when you pick off as many of those types and examples, whether they're the target indications or the devices themselves, that would help to illustrate this: If you could illustrate, when you folks are thinking about device design and engineering and those target indications, what are some of the problems to be solved, technical challenges, opportunities for advancement, questions to answer, things like that, as you think about either the current options available or the work to move the dial of advancement forward.

Sure. So, I'll start with injections. With any ophthalmic delivery technology that requires an injection, the common theme is to be as minimally invasive as possible. So, the delivery system needs to be small and atraumatic to the patient. Trends we see with solid dose delivery are smaller and shorter dose forms, able to be delivered by smaller and shorter needles, for instance. So, minimally invasive is a big focus.

And then the delivery technology also needs to be easy and intuitive for the clinician to administer the treatment. This is oftentimes a single-handed operation where you, potentially, have line-of-sight issues, depending on where you're going in the anatomy.

So, a lot of considerations on the injectors that we develop.

For something like a topical application, such as an eyedrop, one initiative that we've seen a push  towards is preservative-free solutions. So, helping reduce patient exposure to compounds that may have long-term adverse effects. So, that drive puts additional burden on the delivery device and, say, maintaining sterility over time.

And you really need a design that allows easy administration, for instance, not too hard to squeeze, while also minimizing the potential for biological ingress. So, a litany of challenges to work through with those types of products.

Another area where we're seeing more regulatory scrutiny nowadays is the level of cleanliness that is expected for these ophthalmic delivery systems. So, due to the sensitive nature of the anatomy, acceptable limits for things like particulate and endotoxin can be much more stringent than other parenteral injections, which drives the need for manufacturers to implement additional controls to ensure appropriate safety and efficacy of the device.

Not to ask you or invite you to try to give away the proprietary secrets of the sauce there  in terms of how you work on tweaking and honing these devices to address those things you just described. [But] can you illustrate any particular advancement that might show the difference between, say, how the device may have been designed or implemented or thought of, however long back it would have been different than it is today, and what's available today that would illustrate that difference?

I mentioned particulate earlier. New, regulatory guidance [is] coming out where control over particulate is much more stringent than it was before. So, for instance, let's take silicon oil. Silicon oil has been widely accepted as an industry standard for lubrication of needles intended for injection, wherever in the body that might be.

However, for ophthalmic use specifically, silicone oil actually has a propensity for migrating into the anatomy and potentially causing patient complications. You get floaters in the eye when the silicone moves there. So, what alternative solutions might there be to mitigate that particulate concern while also maintaining adequate device performance? The needle still has to be easy to inject into the eye for both the patient comfort and clinician use.

 Good. All right, well, thanks for that illustration, very helpful, appreciate that.

I'm going to throw one more prompt at you, and it's a future-pointing one. I like to end these conversations by looking out over the horizon, whether that's near or far. I guess I'll let you decide how you answer this.

But, as we look out over the horizon of the future state of patient treatment and options for them  and device technologies to help deliver therapies to them, what do you and the other folks at Sanner think about? What questions might you have? What are you yourselves interested in looking at and monitoring and helping to drive forward as you folks look out over that future landscape?

 Sure. I think it's a great question, and I was discussing this with a colleague just a couple of weeks ago. We had, I guess, some curiosities and some thoughts that came up.

So, one of those being,  could future treatments really start to move toward smaller dose formulations that are perhaps locally activated by some mechanism, whether it be the specific biochemistry, light, ultrasound, or similar? Ultimately, I think that could lead to more targeted and less systemic treatment of the disease states, which has benefits.

Another question that came up was, what role might diagnostic technologies play in earlier diagnosis and intervention of these eye diseases? One analogy that we tossed out there is that people used to take statins after a heart attack, but now individuals that are identified as high risk start a lower-dose treatment of those statins earlier on as a preventative measure. And could those preventative diagnostics be better integrated into eye care?

Gotcha. Well, it all sounds very promising. I appreciate the conversation and the updates on the work there. Rob, I want to thank you for joining me. And to our audience at Drug Delivery Leader, I want to thank you for joining for another episode of Supplier Horizons. And we'll see you next time.

About The Featured Guest

Rob Henson is Director of Design and Engineering for Sanner, where he leads medical device programs. Over ten years with Gilero (now Sanner of US), Rob’s experience spans injectable and implantable drug delivery systems, closed-system drug handling, complex fluid circuits, multi-dose inhalers, and design for plastic injection molding. Rob also leads Sanner’s US West Coast Design Center, building a multidisciplinary engineering team and overseeing regional operations and client relationships. Rob is named as an inventor on eight issued patents and several pending applications.