Enable Enfuse: Innovations in On-Body Infusion Technology

Advancements in drug delivery technology have led to the development of on-body infusion systems, offering a more convenient and controlled way to administer medications. These devices benefit patients needing extended or high-volume subcutaneous infusions, reducing clinic visits and improving adherence and comfort.

Enfuse represents a new generation of wearable infusion devices designed for ease of use and precision in medication administration. Understanding its key innovations highlights how these systems enhance drug delivery efficiency and patient experience.

Core Mechanics of On-Body Infusion

On-body infusion systems deliver medication subcutaneously over a controlled period, ensuring a steady absorption profile. Unlike traditional injections that rely on bolus administration, these devices maintain continuous or programmed release, minimizing fluctuations in drug plasma levels. This approach benefits biologics and high-viscosity formulations that require gradual absorption to maintain efficacy while reducing adverse reactions.

The device adheres to the skin using a medical-grade adhesive designed to stay secure without causing irritation. Once activated, a small cannula or microneedle penetrates the epidermis and reaches the subcutaneous tissue, depositing the drug. The depth and angle of insertion are calibrated for optimal absorption, ensuring efficient dispersion into the interstitial fluid. Studies show that controlled subcutaneous infusion enhances bioavailability compared to rapid injections, particularly for large-molecule drugs that rely on lymphatic uptake.

Flow regulation is critical, achieved through mechanical or electronic control mechanisms. Some devices use pressurized reservoirs or spring-driven actuators for consistent infusion, while others incorporate microfluidic pumps that adjust delivery based on pre-programmed parameters. Precision in flow control is essential, as deviations as small as 10% can impact drug efficacy, according to research published in The Journal of Controlled Release.

Components in Enfuse Devices

Enfuse devices integrate multiple components to ensure precise, reliable, and user-friendly drug delivery. These elements maintain controlled infusion rates, optimize drug stability, and enhance patient comfort.

Cartridge and Reservoir

The cartridge and reservoir store the medication and accommodate various formulations, including high-viscosity biologics. These reservoirs are typically made from medical-grade polymers like cyclic olefin copolymer (COC) or silicone-coated glass, chosen for chemical stability and low reactivity with biologic drugs. Maintaining drug integrity is crucial, as proteins and peptides can degrade when exposed to oxygen or leachables from container materials.

To prevent degradation, Enfuse devices incorporate barrier coatings or inert gas overlays to minimize oxidation and maintain sterility. Prefilled reservoirs reduce contamination risks by up to 70% compared to manually filled systems, as noted in Pharmaceutical Research. Reservoir capacity varies, with some models supporting up to 10 mL of medication, making them suitable for extended infusions that would otherwise require multiple injections.

Automated Delivery Mechanism

The automated delivery mechanism ensures consistent drug administration. Enfuse devices use mechanical or electromechanical systems to regulate infusion rates. Spring-driven actuators provide passive, pressure-based delivery, while advanced models incorporate microfluidic pumps or piezoelectric actuators for programmable dosing schedules and real-time adjustments.

Automated delivery accommodates high-viscosity formulations without requiring excessive force. Research in The International Journal of Pharmaceutics shows that microfluidic pump systems can deliver biologics with viscosities exceeding 50 cP while maintaining flow rate accuracy within ±5%. Some Enfuse models include feedback sensors that monitor resistance at the infusion site, adjusting pressure dynamically to prevent occlusions or backflow.

Safety-Release System

The safety-release system prevents accidental drug leakage, premature activation, or improper removal. Enfuse devices use mechanical locks and adhesive-based fail-safes to secure the device until infusion is complete.

A dual-layer adhesive system ensures secure placement, with the inner layer releasing only after the preset infusion duration. Many models incorporate a retractable needle or cannula that withdraws automatically after dosing, reducing the risk of accidental needle sticks. A study in Medical Device and Diagnostic Industry found that retractable needle systems lower post-use injury rates by 85% compared to fixed-needle designs.

Some Enfuse devices also feature audible or visual indicators confirming successful drug delivery, helping users verify full dose administration before removal. These safety mechanisms improve adherence and reduce the risk of incomplete infusions.

Physical Factors Influencing Subcutaneous Delivery

The efficiency of subcutaneous drug delivery depends on factors affecting how medication disperses and reaches systemic circulation. Tissue composition at the infusion site is a key variable. Areas with higher adipose content, like the abdomen, absorb medication more slowly than sites with denser capillary networks, such as the upper thigh. Selecting an appropriate infusion site ensures consistent pharmacokinetics.

Hydration levels and local blood flow also influence drug uptake. Increased circulation, due to physical activity or localized warming, enhances absorption, while vasoconstriction from cold exposure or stress slows it. These fluctuations are particularly relevant for medications with narrow therapeutic windows.

Device mechanics also impact delivery outcomes. Needle or cannula gauge, insertion depth, and angle determine how evenly medication distributes within the subcutaneous layer. Microneedles or flexible cannulas reduce the risk of intramuscular injection, which can alter drug kinetics. Infusion pressure must be balanced to prevent localized pooling, which can cause irritation or nodule formation. Manufacturers calibrate delivery mechanisms to optimize dispersion while maintaining patient comfort.

Pharmacokinetic and Pharmacodynamic Considerations

The effectiveness of on-body infusion systems like Enfuse depends on pharmacokinetics (PK) and pharmacodynamics (PD), which govern drug absorption, distribution, metabolism, and therapeutic effects. Subcutaneous infusion provides steady drug concentrations over time, reducing peak-to-trough fluctuations common with bolus injections. This controlled delivery is crucial for biologics, where maintaining plasma drug levels within a narrow therapeutic range ensures efficacy while minimizing side effects.

A key pharmacokinetic factor is balancing drug clearance with absorption rates. Large-molecule therapeutics rely on lymphatic uptake rather than direct capillary absorption, leading to a slower onset compared to intravenous administration. Infusion rates must be calibrated to prevent saturation of lymphatic transport mechanisms, which could otherwise cause unpredictable bioavailability. Studies in Clinical Pharmacokinetics show that gradual subcutaneous delivery optimizes systemic drug exposure, particularly for monoclonal antibodies and peptide-based therapies.

From a pharmacodynamic perspective, prolonged and stable drug release improves therapeutic outcomes. For conditions such as autoimmune diseases or chronic metabolic disorders, maintaining steady drug-receptor interactions reduces breakthrough symptoms and mitigates side effects linked to fluctuating drug levels. This stability is especially important for therapies with a narrow therapeutic index, where even slight deviations in plasma concentration can affect efficacy and safety.

Material Considerations in Device Construction

The materials used in Enfuse devices ensure durability, biocompatibility, and drug stability. Every component, from the reservoir to the adhesive backing, must maintain structural integrity while minimizing patient discomfort. Chemical compatibility with biologic drugs is a primary concern, as certain polymers can leach compounds that degrade protein-based therapeutics. To prevent this, manufacturers use medical-grade materials like cyclic olefin polymers (COP) or fluoropolymer coatings, which minimize adsorption and reduce drug interactions. These materials also provide excellent moisture and gas barrier properties, preventing oxidation or contamination.

Mechanical properties such as flexibility and tensile strength are also crucial. Since Enfuse is worn on the skin for extended periods, the outer casing must be lightweight yet durable enough to withstand daily activities. Thermoplastic elastomers (TPEs) are commonly used for their ability to conform to body contours without causing irritation. The adhesive layer must provide strong but non-irritating adhesion, balancing secure placement with easy removal. Hydrocolloid-based adhesives are frequently chosen for their moisture-absorbing properties, which help maintain skin integrity and reduce the risk of dermatitis.

By selecting appropriate materials, Enfuse ensures reliability, comfort, and compatibility with a wide range of drug formulations.