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Medical Device and Drug Combination Products for Drug Delivery Systems

4856 words (19 pages) Dissertation

9th Dec 2019 Dissertation Reference this

Tags: Information SystemsMedicalMedical Technology

    Medical device/drug Combination products

As per 21 CFR 3.2(e), combination product is comprised of any combination of a drug and a device; a biological product and a device; a drug and a biological product; or a drug, device, and a biological product. The combination of similar components, such as a drug-drug or a device-device, is not classified as a combination product per FDA regulations.

Combination products are therapeutic and diagnostic products that combine drugs, devices, and/or biological products.

Types of combination products include:

  1. Chemically or physically combined products as per  21 CFR 3.2(e)(1): – Eg: drug-eluting stents, patches, implants with drugs, inhalers, drug pumps, insulin pens
  2. Co-packaged products as per 21 CFR 3.2(e)(2) – Eg: first-aid kits, surgical kits
  3. Cross-labeled products as per 21 CFR 3.2(e)(3) -Eg: photosensitizing drug with light source

Combination products are classified into device, drug, or biologic based on their primary mode of action (PMOA). For eg, a drug-eluting stent is considered a device because its PMOA is to hold open a clogged artery, whereas a skin patch that slowly releases a hormone is considered a drug because PMOA is the hormone drug effect. Each part of the combination product is evaluated individually in addition to evaluating the entire product as a whole. FDA’s medical product centers, which are made up of the Center for Biologics Evaluation and Research (CBER), the Center for Drug Evaluation and Research (CDER), and the Center for Devices and Radiological Health (CDRH) oversee the approval of combination products depending on the classification (“About Combination Products,” n.d.)

In this review development of  medical device/drug combination products in the field of implants, diagnostics and drug delivery systems are summarised.The main drivers for the increasing demand for combination products are customer convenience, evolving medicine models and reimbursement strategies, demand for more outpatient and home-health based services (Brown, n.d.).

1. Implantable drug delivery system

Drug delivery is one of the fastest growing areas for implant applications. Drug release and prosthetic performance are coordinated and designed to work in tandem. Implantable devices are broadly divided based on the purpose into three classes: cardiovascular implants, orthopaedic implants and implants for other use (Khan et al., 2014). Implantable drug delivery system offer features:

  • Steady state of drug release
  • Controlled and tailored delivery of drugs.
  • Site specific/targeted drug administration
  • Significantly lower dose of drug required

1.1 Cardiovascular implants

Drug-eluting stent (DES) is a peripheral or coronary scaffold placed into narrowed, diseased peripheral or coronary arteries that slowly releases a drug to block cell proliferation. DES prevents scar tissue from growing into the artery and prevent the coronary artery from narrowing again.

1.1a  Durable polymer drug-eluting stent

Stent Drug Manufacturer
          XIENCE Family Everolimus Abbott (“XIENCE Alpine Everolimus Eluting Coronary Stent System,” n.d.)
XIENCE V
XIENCE PRIME with bioabsorbable polymer
XIENCE Nano
XIENCE Xpedition
XIENCE PRIME LL
XIENCE Alpine
PROMUS Everolimus Boston Scientific (“Coronary Stents – Boston Scientific,” n.d.)
 TAXUS Express2 Atom
TAXUS Liberte
PROMUS  PREMIER
SYNERGY
Endeavor Sprint Zotarolimus Medtronic (“MedtronicStents.com:Resolute Inegrity,” n.d.)
Resolute  Onyx
Resolute Integrity with BioLinx Polymer

 

1.1bBio absorbable polymer drug-eluting stent

 

Boston Scientific’s SYNERGY coated with Everolimus and Abbot’s Bioresorbable Vascular Scaffold (BVS) known as ABSORB coated with Everolimus are among the gamechangers. They are designed to dissolve into the system within a year to allow the artery to return to normal functioning. Since the stent disappears, it eliminates the cause of potential inflammation that can lead to late-stent thrombosis and restenosis. Most bioresorbable stents are made of polylactic acid. Disadvantages include recoil after expansion,difficulty visualizing a non-metallic stent on fluoroscopy etc (“Bioresorbable Stents Are the Way of the Future,” 2014)

1.2 Orthopaedic implants

Orthopedic implants are primarily designed to support mechanical load in skeleton. Correlating drug delivery with this mechanical support target infection and stimulates the normal bone remodeling process through the release of growth factors. Osteoarthritis and rheumatoid arthritis affect the structure of weight-bearing joints such as the hip and knee. In a total knee arthroplasty, the diseased cartilage surfaces of the lower femur, tibia and the patella are replaced by prosthesis made of metal alloys and polymeric materials. Resorbable calcium phosphate ceramic (CaP) materials,polymers such as methyl-methacrilate as beads or bone cement are used as carrier for antibiotics and growth factors. C alcium phosphate ceramic matrices are suitable carriers for bisphosphonate for bioactive drug delivery system

Drug delivery options used in orthopedic implants are :

  • Coating
  • Biomaterials/cement incorporated in scaffold
  • Beads

Biodegradable devices can be used as a foundation for implant based drug delivery, so that the degradation rate allows for the optimal release of the drug or agent to further assist the healing process. Biomet, Johnson & Johnson, Stryker and Zimmer are the leaders in orthopaedic implant industry.

1.3 Other Implants

1.3a Implantable drug pumps

Implantable drug pumps are used to deliver insulin in the treatment of diabetes, administer pain medications directly to the spine (intrathecal pumps). These are typically programmable active devices that require regular resupply of the medication through an access port. Intrathecal pain pump works more efficiently than oral pain medication because it delivers medicine directly into the cerebral spinal fluid, bypassing the path that oral medication takes through the body. The potency of the medication is about 100-300x more with the pump than when taken orally. The pump is programmed to slowly release medication over a period of time. Pain pump may be a treatment option if other traditional methods have failed to relieve long-term symptoms of chronic pain. This has fewer side effects than oral medication.

Manufacturer Device Drug Intended use
Flowonix Prometra Programmable pump (“Prometra Pump,” 2015) Infumorph implanted drug delivery device to deliver the drug  to intrathecal space via catheter
J&J’s Codman & Shurtleff MedStream Programmable Infusion Pump (“5. MedStream Programmable Infusion Pump | Qmed,” n.d.) morphine / Baclofen
Medtronic SynchroMed infusion system (Medtronic, n.d.) Baclofen

1.3b Ocular Drug Delivery Implants 

Removable or biodegradable ocular inserts can function as controlled-release drug reservoirs. Contact lenses have been used for ocular drug delivery, and their drug-loading capacity can be enhanced by the inclusion of container molecules in their cavities. Ocular implants can provide short-term medication or deliver medication for several years for chronic ocular conditions.

Implant Drug Manufacturer Intended use
Retisert fluocinolone acetonide intraocular implant 0.59 mg  Bausch + Lomb for chronic noninfectious posterior uveitis (“Retisert (fluocinolone acetonide intravitreal implant) 0.59 mg : Bausch + Lomb,” n.d.)
Vitrasert ganciclovir intravitreal implant 4.5 mg  Bausch + Lomb cytomegalovirus retinitis (“Vitrasert ImplantSTERILE INTRAVITREAL IMPLANT WITH CYTOVENE®(GANCICLOVIR, 4.5 MG),” n.d.)
Ozurdex dexamethasone intravitreal implant 0.7 mg Allergan  for macular edema ,central retinal vein occlusion,diabetic macular edema (DME), and posterior uveitis (“OZURDEX® for Diabetic Macular Edema | OZURDEX®,” n.d.)
Iluvien fluocinolone acetonide intravitreal implant 0.19 mg Alimera Sciences diabetic macular edema (“ILUVIEN® (fluocinolone acetonide intravitreal implant) 0.19mg for Diabetic Macular Edema (DME) | Alimera Sciences,” n.d.)

1.3c Contraceptive Devices

Intrauterine devices (IUDs) and intravaginal rings (IVRs), are finding increasing applications in the area of women’s health. Levonorgestrel eluting IUD can aid contraception and treatment for severe menstrual bleeding IVRs are commercially available for contraception, hormone replacement therapy, and to improve the rate ofin vitro fertilization

Implant Drug Manufacturer Features
Kyleena Levonorgestrel Bayer hormone-releasing IUD (intrauterine device) that prevents pregnancy for up to 3/5 years (“Mirena® IUD Homepage | Official Website,” n.d.)
Skyla Levonorgestrel Bayer
Mirena Levonorgestrel Bayer
IMPLANON Etonogestrel Merck Matchstick sized flexible implant inserted under the skin of the inner side  upper arm (“Implanon NXT – Summary of Product Characteristics (SPC),” n.d.)

2. Diagnostics

Rather than simply identifying disease, diagnostics are now used to support clinical development of drugs, predict disease before symptoms begin, forecast the progress of a disorder, and identify patients who are most likely to respond to specific treatments.

 

2.1 Companion diagnostic

As per  FDA final guidance “In Vitro Companion Diagnostic Devices” (Aug. 2014 )

companion diagnostic(CoDx) is defined as in vitro diagnostic device that provides information for the safe and effective use of a corresponding therapeutic product

The uses of CoDx are :

  • Identify population most likely to benefit or most at risk of adverse reaction a particular therapeutic product
  • Monitor response to adjust treatment.
  • Identify population for whom product is known to be safe and effective.

These are tailored for use by physicians to help select the right drugs for the right patients. The test helps a health care professional determine whether a particular therapeutic product’s benefits to patients will outweigh any potential serious side effects or risks (Center for Devices and Radiological Health, n.d.).

Companion diagnostics are developed based on companion biomarkers. Biomarkers are biological indicators that are associated with disease. Certain markers of inflammation, blood clotting, and blood vessel function have been associated with risk of cardiovascular disease, stroke and death. Different classes of biomarkers include somatic mutations, polymorphisms, and gene/protein expression profiles linked  with a particular disease state

Genomic diagnostic tests make use of genetic biomarkers to combine genetic sequencing and clinical information to help oncologists select the right drugs for their patients, based on mutations in cancer-related genes.CoDx helps in integrating  precision medicine in to health care.

2.2a IVD Companion Diagnostic Devices

Drug Device Manufacturer Intended use
Midostaurin LeukoStrat  CDx FLT3 Mutation Assay Invivoscribe Technologies, Inc.  Somatic gene mutation detection system.IVD test for the selection of patients with acute myelogenous leukemia for whom midostaurin treatment is being considered. Detect specific mutations in the FLT3 gene in genomic DNA extracted from mononuclear cells obtained from peripheral blood or bone marrow aspirates of patients diagnosed with AML (“FLT3 Mutation Assay | Invivoscribe,” n.d.)
Rubraca FoundationFocus CDxBRCA Assay Foundation Medicine, Inc. detects sequence alterations in BRCA1 and BRCA2 (BRCA1/2) genes.Test results identifyovarian cancer patients for whom treatment with Rubraca™ (rucaparib) is being considered (“FoundationFocusTM CDxBRCA,” n.d.)
VENCLEXTA  (venetoclax) Vysis CLL FISH probe kit ABBOTT Molecular detects deletion of the LSI TP53 probe target as an aid in identifying those patients with chronic lymphocytic leukemia( CLL) for whom treatment with VENCLEXTA  is indicated (“Vysis CLL FISH Probe Kit | Abbott Molecular,” n.d.)

Table below (Center for Devices and Radiological Health, n.d.)lists some of the FDA approved Breast cancer Companion Diagnostics

Drug Device Manufacturer Methodology
Herceptin INFORM HER2/NEU Ventana Medical Systems FISH
PATHWAY ANTI-HER-2/NEU Ventana Medical Systems IHC
INFORM HER2 Ventana Medical Systems Dual color ISH
PATHVYSION HER-2 Kit Abbott Molecular FISH
INSITE HER-2/NEU Kit BioGenex Laboratories IHC
SPOT-LIGHT HER2 Kit Life Technologies CISH
Bond Oracle HER2 System Leica Biosystems IHC
HER2 Kit Dako Denmark CISH

Abbreviations : FISH –  fluorescence in situ hybridization, ISH –  in situ hybridization,                                      IHC – immunohistochemistry, CISH –  chromogenic in situ hybridization, HER2- human epidermal growth factor receptor

2.2b Imaging Companion Diagnostic Devices

Diagnostic imaging can be used to monitor and improve treatment responses and patient outcomes (Van Heertum et al., 2015).Resonance Health’s  FerriScan R2-MRI Analysis System is an  imaging companion diagnostic for deferasirox to detect liver iron concentration.

The system  measures liver iron concentration to aid in the identification and monitoring of non-transfusion-dependent thalassemia patients receiving therapy with deferasirox (“FerriScan – MRI Measurement of Liver Iron Concentration – Resonance Health,” n.d.).

 

 

 

 

 

 

2.3 Hand held Companion Diagnostic device

These are designed to overcome the challenges in getting diagnostics to patients in remote locations due to extreme temperatures and lack of trained personnel, cost etc.

Device Q-POC point of care device
Manufacturer QuantuMDx
Intended use Hand-held and portable molecular diagnostic device for precision medicine.As a companion diagnostic and for testing  multi-drug-resistant infectious disease including  tuberculosis, HIV/AIDS (“QuantuMDx – Molecular Diagnostics in Minutes,” n.d.)

2.4 Continuous Monitoring Devices – Closed loop sensor and delivery

Smart devices can automate drug delivery in response to real­time patient data. These devices  work like the body’s own systems, continually monitoring relevant biomarkers and releasing appropriate doses of moderating drugs or hormones in response. Combining continuous monitoring and insulin delivery allows diabetics and their physicians to control of patients’ blood sugar in response to the body’s needs. Rather than relying on single data points taken at fixed times, the device continuously monitors blood glucose levels to provide dynamic information about glucose levels.

Device Manufacturer Intended use
MiniMed 670G System Medtronic Artificial pancreas device system.Continuous monitoring and trending of glucose levels. For continuous delivery of basal insulin (at user selectable rates) and administration of insulin boluses (in user selectable amounts) for the management of Type 1 diabetes mellitus  in persons requiring insulin (“MiniMed 670G Insulin Pump System | World’s First Hybrid Closed Loop System,” n.d.)
Accu-Check Combo insulin interactive pump Roche  Combined diagnostics and insulin delivery pumps deliver basal insulin doses and bolus insulin on demand.-high-tech system combining a glucose meter and an insulin pump that communicate via Bluetooth and can be controlled remotely. It even helps patients calculate the best dose. reduce the risk of the long-term complications of diabetes such as kidney disease, sight loss, and heart disease (“Combo system support | Accu-Chek,” n.d.)
PaQ insulin delivery device CeQur Wearable insulin delivery device that delivers up to 3 days of continuous pre-set basal insulin plus on- demand mealtime bolus.This incorporates a disposable insulin reservoir and a reusable insulin monitor. deliver basal insulin doses and bolus insulin on demand (“CeQur PAQ | CeQur SA. / Corporation,” n.d.)

3.  Drug Delivery Devices

3.1 Transdermal delivery systems

  • Dermal Patches provide constant and sustained release profile by properties of capillarity or diffusion/osmosis. Eg: Nicotine and hormone replacement patches
  • Electrodynamic patch – works on the principle of iontophoresis

Electromagnetic field created by the patch generates an ion channel that allows efficient absorption of the active ingredients travelling through the skin.

eg: IontoPatch for pain management  – Single use and disposable iontophoresis patch with built in battery. Self-contained battery produces an electric current to carry drug molecules non-invasively across the skin and to underlying tissue (“IontoPatch® Electronic Transdermal Iontophoretic Drug Delivery System,” n.d.)

3.2 Microneedle Drug Delivery Systems

 

The surface of a substrate or material can be coated with very precise tiny pin-like structures which, when applied to the skin can puncture the dead outer layer creating a micro-channel that allows rapid diffusion of the drug. This is painless and depth of penetration carefully controlled. Solid microneedle technology from 3M  can deliver vaccines or other biologics up to 300 mcg capacity with efficiency better than injection (“Microneedle Drug Delivery Systems | 3M United States,” n.d.).

 

 

 

3.3 Inhalation Drug Delivery

Different types of  Inhalation drug delivery devices are  nebulizers, pressurized metered dose inhalers (MDIs), breath-activated inhalers and emerging novel delivery systems. Adding analytics allows patients and healthcare providers to look for patterns in device usage and biometrics over time. Smart inhaler can analyse the patterns of frequency of use to suggest  need for more aggressive maintenance therapies. Data is analysed to identify early warning signs and patient response to current medication.

Device Manufacturer Features
SmartInhaler Adherium Digital solution for respiratory medication.Sensor and data transmission technologies. mobile app with reporting and reminders (“smartinhaler,” n.d.)
Propeller Propeller Digital platform for respiratory health management. Monitoring device attached to inhalator. Automatically log usage on a mobile app and  transmit data to doctors or caregivers (“Propeller Health | Digital Asthma and COPD Management,” n.d.)

3.4 Scaffold based drug delivery

SurModics, surface modification and drug delivery solutions provider to the medical device industry has exclusive license to two novel classes of biodegradable polymers (PolyActive and OctoDEX) for use in the site specific delivery of drugs from medical devices. PolyActive polymeric drug delivery system is for the controlled release of proteins and lipophilic small molecules for both local and systemic administration. OctoDEX drug delivery system is based on crosslinked dextran microspheres (“Drug Delivery Systems, Drug Delivery Technology: Surmodics Medical Coatings | SurModics: Medical Device Coatings & In Vitro Diagnostics (IVD),” n.d.)

Conclusion

These futuristic devices have the potential to make drug delivery and disease management easier, safer, and convenient for patients and care providers. Overcoming knowledge gaps between the disciplines of technology and medicine is a major problem. Challenges include cybersecurity for connected devices, safety and human factors concerns, and development of the algorithms for drive safe, automated drug delivery. Differences in regulatory pathways for each component of the combination device create an ambiguity in the regulatory processes. There are no universal procedures to follow for harmonized solutions among different countries

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