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Nasal delivery of recombinant human growth hormone with pheroid technology / Dewald SteynSteyn, Johan Dewald January 2006 (has links)
Over the past couple of years there has been rapid progress in the development and design of
safe and effective delivery systems for the administration of protein and peptide drugs. The
effective delivery of these type of drugs are not always as simple as one may think, due to
various inherent characteristics of these compounds.
Due to the hydrophilic nature and molecular size of peptide and protein drugs, such as
recombinant human growth hormone, they are poorly absorbed across mucosal epithelia,
both transcellularly and paracellularly. This problem can be overcome by the inclusion of
absorption enhancers in peptide and protein drug formulations but this is not necessarily the
best method to follow.
This investigation focussed specifically on the evaluation of the ability of the PheroidTM
carrier system to transport recombinant human growth hormone across mucosal epithelia
especially when administered via the nasal cavity. The PheroidTM delivery system is a
patented system consisting of a unique submicron emulsion type formulation. The PheroidTM
delivery system, based on PheroidTM technology, will for ease of reading be called Pheroid(s)
only throughout the rest of this dissertation.
The Pheroid carrier system is a unique microcolloidal drug delivery system. A Pheroid is a
stable structure within a novel therapeutic system which can be manipulated in terms of
morphology, structure, size and function. Pheroids consist mainly of plant and essential fatty
acids and can entrap, transport and deliver pharmacologically active compounds and other
useful substances to the desired site of action.
The specific objectives of this study can be summarised as follows:
a literature study on Pheroid technology;
a literature study on chitosan and N-trimethyl chitosan chloride;
a literature study on recombinant human growth hormone (somatropin);
a literature study on nasal drug administration;
formulation of a suitable Pheroid carrier;
entrapment of somatropin in the Pheroid carrier, and
in vivo evaluation of nasal absorption of somatropin in Sprague-Dawley rats. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2007.
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Nasal delivery of insulin with Pheroid technology / Tanile de BruynDe Bruyn, Tanile January 2006 (has links)
Approximately 350 million people worldwide suffer from diabetes mellitus (DM) and this
number increases yearly. Since the discovery and clinical application of insulin in 1921,
subcutaneous injections have been the standard treatment for DM. Because insulin is hydrophilic
and has a high molecular weight and low bioavailability, this molecule is poorly absorbed if
administered orally.
The aim of this study is to evaluate nasal delivery systems for insulin, using Sprague Dawley rats
as the nasal absorption model. Pheroid technology and N-trimethyl chitosan chloride (TMC)
with different dosages of insulin (4, 8 and 12 IU/kg bodyweight insulin) was administered in the
left nostril of the rat by using a micropipette. Pheroid technology is a patented (North-West
University) carrier system consisting of a unique oil/water emulsion that actively transports drug
actives through various physiological barriers. These formulations were administered nasally to
rats in a volume of 100 p/kg bodyweight in different types of Pheroids (vesicles, with a size of
1.7 1 - 1.94 pm and microsponges, with a size of 5.7 1 - 8.25 pm).
The systemic absorption of insulin was monitored by measuring arterial blood glucose levels
over a period of 3 hours. The TMC formulation with 4 IU/kg insulin produced clinically relevant
levels of insulin in the blood and as a result also the maximal hypoglycaemic effect. TMC is a
quaternary derivative of chitosan and is able to enhance the absorption of various peptide drugs
by opening tight junctions between epithelial cells. Pheroid formulations were also effective in
lowering blood glucose levels but only at higher doses (8 and 12 IU/kg) of insulin. This study
indicated that Pheroid rnicrosponges had a faster onset of action and a slightly better absorption
of insulin when compared to Pheroid vesicles, but many more studies are needed in this field.
Although the results of this study with absorption enhancers are encouraging, nasal insulin
bioavailability is still very low, and the Pheroid formulations and long-term safety of nasal
insulin therapy have yet to be investigated. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2007.
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Nasal drug delivery of calcitonin with pheroid technology / Jeanéne Celesté KotzéKotzé, Jeanéne Celesté January 2005 (has links)
Advances in biotechnology and recombinant technologies have lead to the
production of several classes of new drugs such as peptide and protein drugs.
These compounds are mostly indicated for chronic use but their inherent
characteristics such as size, polarity and stability prevent them from
incorporation in novel dosage forms. The bioavailability of nearly all peptide
drugs is very low due to poor absorption from the administration site. Several
challenges confront the pharmaceutical scientist in developing effective and
innovative dosage forms for these classes of drugs. A lot of attention has
been given to the nasal route of drug administration for delivery of peptide
drugs. The availability of several promising classes of absorption enhancers
and new drug delivery technologies has also prompt scientists to develop new
delivery systems for nasal administration of peptide drugs.
It has been shown in recent years that N-trimethyl chitosan chloride (TMC), a
quaternary derivative of chitosan, is effective in enhancing the absorption of
several peptide drugs, both in the peroral route and in the nasal route of drug
administration. Early indications are that new drug delivery technologies such
as Pheroid technology will also be able to enhance peptide drug absorption in
the nasal route. The aim of this study was to evaluate and compare the
absorption enhancing abilities of TMC and Pheroid technology in the nasal
delivery of calcitonin, a peptide hormone with low bioavailability.
Pheroid vesicles and Pheroid microsponges were prepared and characterized
for their morphology and size distribution. Calcitonin was entrapped into these
vesicles and microsponges and TMC and TMO solutions (0.5 % w/v),
containing calcitonin, was also prepared. These formulations were
administered nasally to rats in a volume of 100 μl/kg body-weight to obtain a
final concentration of 10 IU/kg body-weight of calcitonin. Plasma calcitonin
and calcium levels were determined over a period of 3 hours.
The results of this study clearly indicated that both Pheroid formulations and
the TMC formulation increase the nasal absorption of calcitonin with a
resulting decrease in plasma calcium levels, indicating an increased
absorption of calcitonin. The highest increase in calcitonin absorption was
obtained with the TMC formulation and this was explained by the difference in
the mechanism of action in enhancing peptide absorption between TMC and
Pheroid technology. It was concluded that Pheroid technology is also a potent
system to enhance peptide drug delivery and that the exact mechanism of
action should be investigated further. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2006.
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Nasal delivery of insulin with Pheroid technology / Tanile de BruynDe Bruyn, Tanile January 2006 (has links)
Approximately 350 million people worldwide suffer from diabetes mellitus (DM) and this
number increases yearly. Since the discovery and clinical application of insulin in 1921,
subcutaneous injections have been the standard treatment for DM. Because insulin is hydrophilic
and has a high molecular weight and low bioavailability, this molecule is poorly absorbed if
administered orally.
The aim of this study is to evaluate nasal delivery systems for insulin, using Sprague Dawley rats
as the nasal absorption model. Pheroid technology and N-trimethyl chitosan chloride (TMC)
with different dosages of insulin (4, 8 and 12 IU/kg bodyweight insulin) was administered in the
left nostril of the rat by using a micropipette. Pheroid technology is a patented (North-West
University) carrier system consisting of a unique oil/water emulsion that actively transports drug
actives through various physiological barriers. These formulations were administered nasally to
rats in a volume of 100 p/kg bodyweight in different types of Pheroids (vesicles, with a size of
1.7 1 - 1.94 pm and microsponges, with a size of 5.7 1 - 8.25 pm).
The systemic absorption of insulin was monitored by measuring arterial blood glucose levels
over a period of 3 hours. The TMC formulation with 4 IU/kg insulin produced clinically relevant
levels of insulin in the blood and as a result also the maximal hypoglycaemic effect. TMC is a
quaternary derivative of chitosan and is able to enhance the absorption of various peptide drugs
by opening tight junctions between epithelial cells. Pheroid formulations were also effective in
lowering blood glucose levels but only at higher doses (8 and 12 IU/kg) of insulin. This study
indicated that Pheroid rnicrosponges had a faster onset of action and a slightly better absorption
of insulin when compared to Pheroid vesicles, but many more studies are needed in this field.
Although the results of this study with absorption enhancers are encouraging, nasal insulin
bioavailability is still very low, and the Pheroid formulations and long-term safety of nasal
insulin therapy have yet to be investigated. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2007.
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Nasal drug delivery of calcitonin with pheroid technology / Jeanéne Celesté KotzéKotzé, Jeanéne Celesté January 2005 (has links)
Advances in biotechnology and recombinant technologies have lead to the
production of several classes of new drugs such as peptide and protein drugs.
These compounds are mostly indicated for chronic use but their inherent
characteristics such as size, polarity and stability prevent them from
incorporation in novel dosage forms. The bioavailability of nearly all peptide
drugs is very low due to poor absorption from the administration site. Several
challenges confront the pharmaceutical scientist in developing effective and
innovative dosage forms for these classes of drugs. A lot of attention has
been given to the nasal route of drug administration for delivery of peptide
drugs. The availability of several promising classes of absorption enhancers
and new drug delivery technologies has also prompt scientists to develop new
delivery systems for nasal administration of peptide drugs.
It has been shown in recent years that N-trimethyl chitosan chloride (TMC), a
quaternary derivative of chitosan, is effective in enhancing the absorption of
several peptide drugs, both in the peroral route and in the nasal route of drug
administration. Early indications are that new drug delivery technologies such
as Pheroid technology will also be able to enhance peptide drug absorption in
the nasal route. The aim of this study was to evaluate and compare the
absorption enhancing abilities of TMC and Pheroid technology in the nasal
delivery of calcitonin, a peptide hormone with low bioavailability.
Pheroid vesicles and Pheroid microsponges were prepared and characterized
for their morphology and size distribution. Calcitonin was entrapped into these
vesicles and microsponges and TMC and TMO solutions (0.5 % w/v),
containing calcitonin, was also prepared. These formulations were
administered nasally to rats in a volume of 100 μl/kg body-weight to obtain a
final concentration of 10 IU/kg body-weight of calcitonin. Plasma calcitonin
and calcium levels were determined over a period of 3 hours.
The results of this study clearly indicated that both Pheroid formulations and
the TMC formulation increase the nasal absorption of calcitonin with a
resulting decrease in plasma calcium levels, indicating an increased
absorption of calcitonin. The highest increase in calcitonin absorption was
obtained with the TMC formulation and this was explained by the difference in
the mechanism of action in enhancing peptide absorption between TMC and
Pheroid technology. It was concluded that Pheroid technology is also a potent
system to enhance peptide drug delivery and that the exact mechanism of
action should be investigated further. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2006.
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Nasal delivery of recombinant human growth hormone with pheroid technology / Dewald SteynSteyn, Johan Dewald January 2006 (has links)
Over the past couple of years there has been rapid progress in the development and design of
safe and effective delivery systems for the administration of protein and peptide drugs. The
effective delivery of these type of drugs are not always as simple as one may think, due to
various inherent characteristics of these compounds.
Due to the hydrophilic nature and molecular size of peptide and protein drugs, such as
recombinant human growth hormone, they are poorly absorbed across mucosal epithelia,
both transcellularly and paracellularly. This problem can be overcome by the inclusion of
absorption enhancers in peptide and protein drug formulations but this is not necessarily the
best method to follow.
This investigation focussed specifically on the evaluation of the ability of the PheroidTM
carrier system to transport recombinant human growth hormone across mucosal epithelia
especially when administered via the nasal cavity. The PheroidTM delivery system is a
patented system consisting of a unique submicron emulsion type formulation. The PheroidTM
delivery system, based on PheroidTM technology, will for ease of reading be called Pheroid(s)
only throughout the rest of this dissertation.
The Pheroid carrier system is a unique microcolloidal drug delivery system. A Pheroid is a
stable structure within a novel therapeutic system which can be manipulated in terms of
morphology, structure, size and function. Pheroids consist mainly of plant and essential fatty
acids and can entrap, transport and deliver pharmacologically active compounds and other
useful substances to the desired site of action.
The specific objectives of this study can be summarised as follows:
a literature study on Pheroid technology;
a literature study on chitosan and N-trimethyl chitosan chloride;
a literature study on recombinant human growth hormone (somatropin);
a literature study on nasal drug administration;
formulation of a suitable Pheroid carrier;
entrapment of somatropin in the Pheroid carrier, and
in vivo evaluation of nasal absorption of somatropin in Sprague-Dawley rats. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2007.
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