5 Aptamer-Based Medical Devices
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will continue to increase at a CAGR of 4.5% with expenditure of $39 billion expected
by 2024 [3].
The USA is the world’s largest producer and consumer of medical devices,
accounting for around 40% of the world’s total production and consumption. The
FDA is part of the public health service of the state health and service department. It
is responsible for the regulation of all foods, drugs, cosmetics and medical devices
in the USA. It is also the first consumer protection agency in the USA. FDA has a
huge influence in the USA and even all around the world. Its reputation and professional level are deeply trusted by experts and the general public. Therefore, many
international manufacturers seek to obtain FDA certification as the highest honor
and guarantee of product quality.
FDA regulates medical devices and oversees their manufacture, packaging, and
distribution in compliance with the law. According to the medical use and possible
harm to human body, the medical apparatus and instruments can be divided into Class
I, II, and III, among which the control of Class III medical devices is the strictest.
A postamendment device is one that was first distributed commercially on or after
May 28, 1976. Postamendment devices determined by FDA to be not substantially
equivalent to either preamendment devices or postamendment devices classified into
Class I or II are “new” devices and fall automatically into Class III. Before such
devices can be marketed, they must have an approved premarket approval application
(PMA) or be reclassified into Class Ior Class II [5]. According to the above rules of
FDA, an aptamer-based medical device is classified as Class III due to its novel core
recognition elements, and generally needs to get an approved PMA, which contains
sufficient valid scientific evidence to assure that the device is safe and effective for
its intended use(s). A rigorous and successful clinical trial is one of the prerequisites
for getting a PMA.
Aptamers are single-stranded DNA or RNA molecules selected by systematic
evolution of ligands by exponential enrichment (SELEX), with specific recognition
abilities to their targets [6]. They can fold into complex three-dimensional shapes,
forming binding pockets and clefts for the specific recognition and tight binding
of targets from metal ions and small molecules to large proteins and higher order
protein complexes, and even whole cells, viruses, parasites [7, 8]. They not only can
be applied as probes of biosensing and molecular recognition but also have potential
in diagnosis, treatment and clinical test. But because of the strict approval procedures
of medical devices, to our knowledge, there is no officially approved aptamer-based
medical device in the market so far. Theoretically, aptamers are functionally comparable to antibodies and even termed as “chemical antibodies” owing to their ease
in chemical synthesis and modification. Besides, aptamers offer several advantages,
including their relatively small physical size, high stability, lack of immunogenicity
and obviating the use of host animals [9]. Based on the above characteristics, aptamers
are potential alternatives to long-established antibody-based biotechnological products for diagnostics and therapy in the field of medical devices. From the above,
in this chapter, we will introduce some clinical trials, patents and papers related to
the highly potential prototypical aptamer-based medical devices from two aspects:
“diagnosis” and “therapies.”
117
will continue to increase at a CAGR of 4.5% with expenditure of $39 billion expected
by 2024 [3].
The USA is the world’s largest producer and consumer of medical devices,
accounting for around 40% of the world’s total production and consumption. The
FDA is part of the public health service of the state health and service department. It
is responsible for the regulation of all foods, drugs, cosmetics and medical devices
in the USA. It is also the first consumer protection agency in the USA. FDA has a
huge influence in the USA and even all around the world. Its reputation and professional level are deeply trusted by experts and the general public. Therefore, many
international manufacturers seek to obtain FDA certification as the highest honor
and guarantee of product quality.
FDA regulates medical devices and oversees their manufacture, packaging, and
distribution in compliance with the law. According to the medical use and possible
harm to human body, the medical apparatus and instruments can be divided into Class
I, II, and III, among which the control of Class III medical devices is the strictest.
A postamendment device is one that was first distributed commercially on or after
May 28, 1976. Postamendment devices determined by FDA to be not substantially
equivalent to either preamendment devices or postamendment devices classified into
Class I or II are “new” devices and fall automatically into Class III. Before such
devices can be marketed, they must have an approved premarket approval application
(PMA) or be reclassified into Class Ior Class II [5]. According to the above rules of
FDA, an aptamer-based medical device is classified as Class III due to its novel core
recognition elements, and generally needs to get an approved PMA, which contains
sufficient valid scientific evidence to assure that the device is safe and effective for
its intended use(s). A rigorous and successful clinical trial is one of the prerequisites
for getting a PMA.
Aptamers are single-stranded DNA or RNA molecules selected by systematic
evolution of ligands by exponential enrichment (SELEX), with specific recognition
abilities to their targets [6]. They can fold into complex three-dimensional shapes,
forming binding pockets and clefts for the specific recognition and tight binding
of targets from metal ions and small molecules to large proteins and higher order
protein complexes, and even whole cells, viruses, parasites [7, 8]. They not only can
be applied as probes of biosensing and molecular recognition but also have potential
in diagnosis, treatment and clinical test. But because of the strict approval procedures
of medical devices, to our knowledge, there is no officially approved aptamer-based
medical device in the market so far. Theoretically, aptamers are functionally comparable to antibodies and even termed as “chemical antibodies” owing to their ease
in chemical synthesis and modification. Besides, aptamers offer several advantages,
including their relatively small physical size, high stability, lack of immunogenicity
and obviating the use of host animals [9]. Based on the above characteristics, aptamers
are potential alternatives to long-established antibody-based biotechnological products for diagnostics and therapy in the field of medical devices. From the above,
in this chapter, we will introduce some clinical trials, patents and papers related to
the highly potential prototypical aptamer-based medical devices from two aspects:
“diagnosis” and “therapies.”