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PRODUCT MONOGRAPH

CYSTIC FIBROSIS
CONTENTS
Current situation 3
Two pathogenic hypotheses 4
BRONCHIECTASIS 5
HYPERTONIC SALINE SERUM
HYANEB
Rationale of use 6
Clinical data 9
Limits 14
The product 15
Hyaluronic acid 17
Clinical experience 18
References 23

CYSTIC FIBROSIS
Current situation
The treatment of cystic fibrosis has made major progress in the last 20 years,
as is demonstrated by current life expectancy, significantly higher than only 10
years ago, and also by the better quality of life enjoyed by most patients.
This progress is due to several aspects:
• The improvement of nutritional intake.
• The streamlining of antibiotic treatment by the inhaled route.
• The integrated therapeutic approach, with mucoactive, antiinflammatory
and antibiotics.
• Greater aggressiveness in the eradication of Pseudomonas aeruginosa.
• Greater attention to patient isolation procedures to avoid cross
contagion.
Increase in survival and progress
made in investigation in the last 20 years.
FIG. 1
According to general opinion, as of this moment, progress in pharmacologic
treatment will be inevitably subject to the development of molecules that can
act on the functional defect, in other words, on the cystic fibrosis
transmembrane conductance regulator, CFTR protein or ion channels.
Only by acting on underlying pathogenic mechanisms will it be possible to
accomplish a relevant improvement reflected in the prolongation of survival
and increased quality of life (3).
In fact, it is difficult to envisage that treatments targeting secondary
symptoms will improve prognosis and quality of life.

Two pathogenic hypotheses
Two hypotheses have been established to explain the cascade of pathogenic
phenomena that determine the two most-feared complications of cystic
fibrosis: chronic infection and inflammation.
Hypothesis I
• The alteration in transmembrane ion transport drastically reduces the
layer of periciliary fluid (PCL), which in normal circumstances generates
a suitable environment for the cilia to move properly and eliminate the
mucus. This reduction prevents the direct interaction of the mucus with
the epithelium and its adhesion. The reduction in PCL gives rise to the
formation of mucus plugs and generates the ideal substrate for bacterial
growth.
Hypothesis II
• The other pathogenic hypothesis, relates chronic infection to deficiency in
chlorine transport through the CFTR, holds that alterations in the
aqueous layer of the airway surface reduce the bactericidal capacity of
the substances produced by the respiratory epithelium.
The first hypothesis attributes the main function of protection of the airways
from infections to mucociliary clearance, whereas in the second case the
protective factors produced directly by the epithelium are assumed to play a
more outstanding role (2-6).
Regardless of the hypothesis posed, be it the reduction in bacterial elimination
or deficiency of bactericidal capacity in the respiratory epithelium, which gives
rise to bacterial colonisation and ultimately chronic infection, the common
denominator is always dehydration of the respiratory tree and reduction in the
fluid layer that covers the respiratory epithelium.
Thus, the moisturisation of the airways and the recovery of a suitable fluid
layer may prove to be fundamental in avoiding infectious progression and
functional deterioration of patients.
FIG. 2
The moisturisation of the airways and the recovery, at least partial, of
the fluid layer, can prevent or reduce pulmonary deterioration.

BRONCHIECSTASES
Unlike cystic fibrosis, there has been less research into the treatment of
bronchiecstases, there are no consensus conferences that facilitate
management, and control is frequently performed in non-specialised units (7).
Patients with bronchiecstases usually have an increased production of mucus
persistently, and have a disorder in the mucociliary transport system.
Disorder of the mucociliary system is related fundamentally to a modification in
the amount and the properties of the bronchial mucus, with a surplus of mucin
with regard to its water content, albeit also with slower mobilisation (8, 9).
The disequilibrium between the mucin and the water content of the bronchial
mucus gives rise to a reduction in the layer of PCL and creates a layer of
adherent mucus, difficult to eliminate (10).
Similarly, the concentrations of sodium and chlorine in the sputum produced
by bronchiecstatic patients are below those found in plasma and also below the
optimal concentrations for suitable clearance (11).
The failure of the mucociliary system to clear the airways leads to the
accumulation of mucus, to the obstruction of the airways, bacterial colonisation
with recurring infectious exacerbations and to an increase in the morbidity and
mortality of patients with bronchiecstases.
Not only does the increase in water in the airways optimize the amount
of PCL, it also improves the moisturisation of the mucus, which facilitates
mucociliary clearance in these patients (12).
The increase in water in the airways optimizes the amount of PCL
improves the moisturisation of the mucus, which facilitates
mucociliary clearance in patients with bronchiecstases

HYPERTONIC SALINE SERUM
Rationale of use
In the airways, healthy individuals have a fluid layer, maintained by means of
an equilibrium between the secretion of chlorine and the absorption of sodium,
which lines the surface of the cells of the respiratory epithelium. This layer is
covered, in turn, by a fine layer of mucus secreted by the glands of the
mucosa. The layer of mucus moves, due to cilia of the respiratory mucosa cell
surface, from the lower to the upper airways.
The fluid layer guarantees sufficient viscosity for the cilia to be able to move
effectively and for the mucus to move as well (13).
In cystic fibrosis, the defective secretion of chlorides and the hyperabsorption
of sodium give rise to a reduction in the fluid layer present on the surface of
the airways and therefore a deficit in mucociliary clearance and airway
defences.
For these reasons, research in cystic fibrosis is focusing on drugs that can
condition the transport with a view to restoring the functioning of the CFTR,
stimulating the release of chlorine or inhibiting sodium absorption, together
with the use of osmotic substances to moisturise the airways (14).
In patients with bronchiecstases, bronchial secretions are characterised by a
greater concentration of mucin (10) and by a reduction in chlorine and sodium
concentrations (11). This disequilibrium increases the viscosity and adherence
of the mucus to the airways and reduces the amount of PCL, reducing the
efficacy of ciliary movement and facilitating the accumulation of mucus.
Osmotic flow from the submucosa to the airway surface in the
presence of an osmotic agent in cystic fibrosis (FIG 3)

The balance between Na+ absorption and Cl- secretion ensures maintenance of an aqueous layer in the
respiratory epithelium:
A.-The mucus is transported through the airway due to ciliary movement
B- In Cystic fibrosis, ion exchange deficit leads to the loss of the aqueous layer and reduces the mucociliary
clearance.
C.-The Hypersaline solution through osmotic action, retains water, restores the aqueous layer and improves
mucociliary clearance.
The administration of osmotic substances, such as a hypertonic solution of
sodium chloride, makes it possible to increase the volume of the airway fluid
layer, creating a flow of water and restore, at least partially, mucociliary
function (15).
The increased concentration of sodium chloride on the surface of the airways
produces a gradient for water transport, which moves through the water
channels in the opposite direction to that of the active transport (5).
This generates an osmotic flow from the submucosa to the airway surface. FIG
3
By means of the osmotic force, hypertonic saline solution increases the volume
of fluid on the airway surface, re-establishes mucociliary clearance and
improves pulmonary function in cystic fibrosis patients (16).
The evident symptomatic effect of a treatment with hypertonic saline solution
is the increase in the amount of mucus expectorated, with a less dense and
more hydrated appearance in cystic fibrosis and bronchiectasis patients. Even
so, the mucoactive action is not the main effect of hypertonic saline solution on
the airways.
In fact, hypertonic saline solution favours the recovery of more physiological
conditions, producing an increase in the thickness of the PLC and chlorine
content, which translates into a less favourable environment for bacterial
colonisation and for the development of chronic infection (5).
Hypertonic saline solution does not act directly on the mucus, but
rather facilitates expectoration, acting on the main cause that

determines its stagnation.
In healthy people, the normal flow of water guarantees the formation of PCL,
and mucus clearance is performed at a rate of 60 micrometres per second.
In the CF patient, the deficient secretion of chloride and the increase in the
absorption of sodium give rise to dehydration of PCL, the absence of
mucociliary clearance, and halts the movement of the mucus in the airways. In
patients with bronchiecstases, the reduction in mucociliary clearance is due
to a disequilibrium between the concentration of mucin and water in the
respiratory secretions, which also leads to a reduction in PCL.
The inhalation of hypertonic saline solution regenerates normal water flow by
means of an osmotic mechanism, thus restoring mucociliary clearance and
guaranteeing an even greater transport speed than physiological speed; FIG. 4
(5).
FIG. 4
Alteration of ion transport in CF
and action of hypertonic saline solution
The guidelines of the Cystic Fibrosis Foundation recommend chronic treatment
with nebulised in hypertonic saline solution in patients as of 6 years of age to
improve pulmonary function, and reduces exacerbations (17).
The regular use of hypertonic serum generates less propitious
conditions for colonisation by pathogens.

Outcomes in clinical studies
Patients with cystic fibrosis
The short-term administration of hypertonic serum is capable of improving
rheological properties and mucus mobility, as well as the moisturisation of the
airway surface, mucociliary clearance and pulmonary function of patients with
cystic fibrosis (18).
An in vitro and ex vivo study (4) has demonstrated that hypertonic saline
solution exercises a prolonged effect on the amount of liquid of the surface of
epithelial cells extracted from patients with cystic fibrosis, besides a
maintained improvement in mucociliary transport.
Although the mechanism of this prolonged effect has yet to be clarified, on the
basis of these observations it follows that nebulised hypertonic saline solution
constitutes a possible therapeutic option to restore airway surface fluid in
patients with cystic fibrosis (18).
At the beginning of treatment there is abundant expectoration of dense mucus,
which tends to normalise with the passing of time and with the continuation of
treatment, with increasingly less purulent mucus.
A randomised and double blind Australian study performed on a broad sample
of patients above the age of 6 years with CF (n = 164) compared twice-daily
nebulisation and 48 weeks of 7% hypertonic saline serum and physiological
serum (control).
The group treated with hypertonic saline serum presented fewer exacerbations
(–56%; p = 0.02) and a significantly higher percentage of patients without
exacerbations (76%; p = 0.03). The duration of the study and the sample size
reinforce this study's confirmation of the already well-known properties of
hypertonic solution.
The reduction in exacerbations and infection-free time confirm the capacity of
the hypertonic saline solution to hamper the development of conditions
favourable to infection.
In the study, no statistically significant differences were observed between
both groups in terms of the percentage of change of pulmonary function
measured both in forced vital capacity (FVC) and in forced expiratory volume
in 1 second (FEV1) or in maximum expiratory flow of 25% to 75% of the FVC
(MEF25-75). However, the absolute difference in pulmonary function between
the groups in week 48 of the treatment was significant (P=0.03). Compared to
the control group, the group with hypertonic solution had a significantly higher
FVC and FEV1 (FIG. 5).

FIG 5 Evolution of FVC and FEV1 for 48 weeks
FIG. 5. Absolute variation in the forced vital capacity (FVC) (figure A) and FEV1 with regard to
the baseline value (figure B).
The values were corrected at baseline FEV1 values according to age, weight and gender as
covariables.
The significance values and 95% confidence intervals are presented.
FIG. 6
Exacerbation-free survival
FIG. 6. The time interval during which the patients remained free of exacerbations was
significantly more prolonged in the group treated with hypertonic saline solution than in the
control (p = 0.03) group, with a respective percentage of exacerbation-free survival of 76%
and 62% over the 48 weeks.

The study demonstrates the long-term efficacy of the hypertonic saline solution
7 %. The 48-week twice daily nebulised treatment gave rise to a significant
improvement in respiratory function (Fig. 5), a reduction of infectious
exacerbations (Fig. 6) and a reduction of school and work absenteeism (18).
The infectious exacerbations are responsible of the pulmonary disease
progression in theses patients and are therefore regarded as a very predictive
element of morbidity and mortality.
Another important study on inhaled hypertonic solution serum was performed
with 24 patients with cystic fibrosis assigned randomly to treatment with 7%
hypertonic serum, preceded by administration of an oral placebo, or treatment
with the same solution preceded by the administration of amiloride, a molecule
that inhibits water permeability in the airways. Mucociliary clearance and
pulmonary function were measured in all patients by means of the evaluation
of FEV1, both at baseline visit and one hour after inhalation, and mucociliary
clearance according to the «rate of mucus clearance in one hour».
At the end of treatment, the group treated with hypertonic solution and
placebo presented an improvement in mucociliary clearance maintained over
time (p = 0.02), as well as improved pulmonary function, unlike the group
treated with amiloride and hypertonic solution, in which no improvement was
observed, either in clearance or respiratory symptoms.
In fact, amiloride reduced the beneficial effects of the administration of
hypertonic solution, thus indirectly confirming that it is very important to
inhale a high concentration of salts and that the benefit of hypertonic serum is
explained by moisturisation through the airways. This moisturisation
facilitates clearance of the mucus and restores the physiological
conditions altered by the genetic defect inherent in cystic fibrosis.
Thus, besides providing more clinical data on the efficacy of nebulised
hypertonic saline serum, the authors shed some light on the mechanism of
action. Hypertonic saline serum is capable of improving water transport in the
airways, helping to restore the fluid layer of the epithelium, which permits
proper ciliary movement, thus improving mucus clearance (16).
Treatment with hypertonic solution has been efficacious in all stages of the
disease, although it is the newly-diagnosed patient who can benefit most from
the treatment, since it prevents, or at least delays, loss of functionality.
Nevertheless, even in patients whose respiratory function is already
compromised, treatment with hypertonic serum may reduce the number of the
infectious exacerbations.
Similarly, since viral infections give rise to a reduction in PCL in the parts of
the respiratory tree which maintain normal moisturisation, hypertonic saline
serum can be used to preserve these areas, preventing the extension of
chronic infection (20).

The numerous experimental and clinical data all attribute the following effects
to the hypertonic saline solution in cystic fibrosis patients:
• Increase in mucociliary clearance (16-18).
• Improvement of pulmonary function (18-19).
• Reduction in exacerbation frequency (18).
• Reduction in children and adult absenteeism (18).
Hypertonic saline solution is regarded as an integral part of the
treatment of cystic fibrosis, since it prevents the development of
obstructive symptoms in incipient phases and delays lung
deterioration in patients with already compromised clinical symptoms.
Treatment with hypertonic saline serum has also been studied in very young
children as of the age of four months, and it has been demonstrated to be
efficacious and is tolerated well enough even in this category of paediatric
patients (19), for whom early treatment represents an important condition in
the prevention of the development of chronic infection and delayed
dysfunction.
Regular treatment from an initial stage of the disease may prevent
infection and add years of life.

Patients with bronchiecstases
Elimination of sputum is of vital importance in the care of patients with
bronchiecstases. Disease progression is closely related to sputum retention,
which leads to a vicious circle of infection, inflammation and greater sputum
production.
The efficacy of hypertonic saline solution with physiotherapy was studied in 24
patients with bronchiecstases that presented expectoration difficulty. These
patients were distributed randomly to be given four regimens of physiotherapy
in a randomised sequence.
In this study, it was observed that after the inhalation of a 7% hypertonic
solution, the weight of the sputum was significantly greater (P=0.002),
patients reported greater ease of expectoration and the sputum had less
viscosity than following the inhalation of the isotonic solution (p=0.008)(11).
Clinically, these results are important, since if the patients find expectoration
easier, the implementation of physiotherapy will be easier, more effective and
less tiring, which will result in better treatment compliance.
The improvement in mucociliary clearance seen after the administration of
hypertonic solution may be due to the increase in the salt concentration in the
retained secretions. This increase in salt concentration promotes the
moisturisation of the bronchial mucus and particularly of the PCL, improving
interaction with the cilia and increasing mucociliary clearance.
The results of this study demonstrate that the inhalation of 7% hypertonic
solution achieves, in patients with stable bronchiecstases:
Increased sputum production
Reduction in sputum viscosity
Easier expectoration

THE LIMITS OF HYPERTONIC SALINE SERUM
As a rule, treatment with hypertonic serum is well tolerated, although it should
always be given following premedication with bronchodilator, a
circumstance which does not always prevent the appearance of
bronchoconstriction phenomena.
In many patients, the inhalation of hypertonic serum gives rise to cough
(which may reach moderate intensity), mucosa irritation and an unpleasant
salty taste that lingers in the throat, even after inhalation: this sensation is
regarded as an important cause of the progressive reduction in therapeutic
compliance observed over time.
The inhalation of hypertonic serum is a treatment that should be given
chronically (even lifelong), hence tolerability and acceptability are
fundamental aspects that largely condition therapeutic compliance and
therefore efficacy.
In fact, there are many patients who, even after a good initial response,
interrupt treatment due to tolerability problems or because they find it
unpleasant.
Bronchoconstriction
phenomena
Cough Irritation of the
mucosa
Unpleasant salty taste
in the throat
Reduction in compliance

HYPERTONIC SERUM
7% NaCl and 0.1% SODIUM
HYALURONATE
HYANEB is a new formulation that makes it possible to fully enjoy the
moisturising properties of hypertonic solution and at the same time minimise
both the undesirable effects and the unpleasant taste.
HYANEB reduces
the irritant effects of hypertonic solution
the unpleasant salty taste
This result was achieved thanks to the merging of sodium hyaluronate,
which, besides its peculiar properties, presents the advantage of being a
macromolecule, and therefore does not modify the hypertonicity of the solution
or its efficacy (22).
HYANEB
maintains the osmotic properties of the hypertonic solution
unchanged

The concentration of sodium chloride (7%) of Hyaneb proved to be the most
efficacious one in the different studies performed, as confirmed, among other
works, by the recent Cochrane revision (21) titled Nebulised hypertonic saline
for cystic fibrosis, which highlights that research geared towards evaluating the
mucociliary clearance of hypertonic serums at concentrations between 3% and
12%, by means of measuring the clearance of a radioisotope taken in the
inhaled form, have found a statistically significant difference in efficacy
between the 3% concentration and the 7% concentration, but not between the
7% and the 12% (21).
The hyaluronic acid contained in Hyaneb is characterised by a molecular weight
of 300-500 kD and a concentration of 0.1%.
It was determined that this concentration and molecular weight of hyaluronic
acid optimises inhalation of the formulation, its moisturising action and its
capacity to mitigate the adverse effects of the inhalation of hypertonic serum.
Hyaneb is available in a single presentation of 30 single-use vials. Each
pack contains 6 strips with 5 vials each. The vials are made of
transparent polyethylene with a volume of 5 ml, sterile, are ready to
be used and contain no preservatives.
HYANEB BOX IMAGE
HYANEB
it is supplied ready for use
it is sterile
it does not contain preservatives
it is single-use
it is manufactured according to the standards of BPF
HYANEB
is compatible with pressurised and vibration-based systems
THE USE OF A PARI BOY AND TURBO BOY COMPRESSOR AND A PARI LC PLUS NEBULISER
IS RECOMMENDED. AN EFLOW RAPID NEBULISER CAN BE USED AS ALTERNATIVE

HYALURONIC ACID
Hyaluronic acid belongs to the family of the glucosaminoglycans, and its
molecule is comprised of a linear chain (non-ramified) containing a repeat
series of disaccharide units comprised of glucuronic acid and N-acetylglucosamine,
bound by glycoside chains.
Hyaluronic acid has the unique capacity of binding to a large number of
water molecules and retaining them in the interfibrillary spaces, so that it is
a fundamental part of the liquid colloidal matrix of the conjunctive tissue and
has important effects on tissue morphogenesis (22).
FIG.8 Hyaluronic acid
In serum, the concentrations of hyaluronic acid are 10-100 μg/l, whereas the
skin, intestine and lungs contain more than 50% of all the body's hyaluronic
acid. In the lungs, the content of hyaluronic acid varies between 15 and
150 μg per gram of dry weight and is localised particularly in the
peribronchial, interalveolar and perialveolar tissue, it is drained by the lymph
vessels and is catabolised in the local nodes and the liver (23).
Moreover, hyaluronic acid is an important structural element of elastin and
collagen fibres.
Thanks to its physical and chemical characteristics, Hyaluronic acid is known to
perform different biological functions in animal tissues. Mainly, it maintains the
degree of moisturisation, turgor, plasticity and viscosity, since its distribution
in the space allows it to accumulate a considerable number of water molecules;
it works as a filter against the free diffusion of determined substances or
bacteria and infectious agents, with the added capacity of neutralising the
action of elastase (24) and protecting elastic fibres from degradation.
Hyaluronic acid also has healing and anti-inflammatory properties (25, 26).

In the airways, Hyaluronic acid intervenes in the mechanism of defence on
stimulating the movement of the cilia by binding to a receiver located in
the apical part of the ciliated epithelial cells and reinforcing the elimination of
foreign material from the mucosa surface, whereas at the same time it
regulates and retains the apical surface of important enzymes for homeostasis,
preventing them from being carried away by ciliary movement (31).
More recently, hyaluronic acid's capacity to inhibit the release of elastase
by neutrophils and macrophages has been demonstrated, a situation that
normally occurs in pulmonary inflammation.
It seems that this mechanism would be related to a possible barrier function of
hyaluronic acid versus elastase, thanks to which it would protect the lung
tissue from enzyme attack.
More specifically, preliminary studies have been carried out on the activity of
hyaluronic acid in obstructive disease models such as emphysema, COPD and
asthma.
Physiological properties and functions of hyaluronic acid:
o Moisturising action
o Protective effect versus lythic enzymes
o Reduction in bronchoconstriction
o Stimulation of ciliary movement
o Regulation and retention of enzymes that are
important for homeostasis
The aforementioned characteristics and properties endorse the use of
hyaluronic acid in the formulation of Hyaneb to improve the tolerability and the
acceptability of hypertonic saline solution.
The protection of the respiratory mucosa against the irritant effects of the high
saline concentration and moisturising properties make hyaluronic acid a perfect
ally for hypertonic saline solution.

Hyaneb in clinical practice
A comparative clinical study was performed between HYANEB and a
conventional hypertonic saline serum (34).
Patients and methods
Crossover, control and single-blind study. Twenty patients with CF inhaled the
two formulations under masking, with a difference of 24 hours between each
administration, and treatment was reversed after the first inhalation.
The patients were asked to rate the following parameters:
Cough
Irritation of the mucosa
Unpleasant salty taste in the mouth
The score was expressed as follows:
absent 0
mild 1
moderate 2
intense 3
Patients were also asked to express their opinion on acceptability/satisfaction
on a scale of 1 to 5:
acceptability/satisfaction 1- 5

Results
Assessment of the symptoms: cough, irritation of the throat, salty
taste in the mouth
Cough: The inhalation of conventional hypertonic solution produced cough in
18 of the 20 patients (90%) immediately after treatment, with an overall score
of 32. The inhalation of HYANEB® produced cough immediately after
treatment in 7 of the 20 patients (35%), with a overall score of 8. Pharyngeal
irritation: Pharyngeal irritation occurred in 14 of the 20 patients (70%) after
the administration of conventional hypertonic solution, with an overall score of
23. Pharyngeal irritation, on the other hand, only occurred in one of the 20
patients (5%) after the administration of HYANEB®, with an overall score of 2.
Unpleasant sensation of salt in the mouth: all patients (100%) treated with
conventional hypertonic solution complained about the taste of salt, whereas
only 2 out of 20 (10%) reported this effect after the administration of
HYANEB® The overall score with hypertonic solution was 32, and with
HYANEB® it was 3 (Fig. 9 and 10).
Patients (%)
0 20 40 60 80 100
Patients that report the symptoms
cough throat irritation salty taste in the
mouth
HYANEB
HSS
HYANEB Hypertonic solution
Cough 7/20 18/20
Irritation of the throat 1/20 14/20
Unpleasant salty taste in the mouth 2/20 20/20

35
30
25
20
15
10
5
0
Total score of the 3 symptoms evaluated
cough throat irritation salty taste in the mouth
HYANEB
HYANEB Hypertonic solution
Cough 8 32
Irritation of the throat 2 23
Unpleasant salty taste in the
mouth
3 32
Assessment of the opinion of satisfaction with the product expressed
by the patients
5
4
3
2
1
0
Product satisfaction opinion
OPINION OF SATISFACTION WITH THE PRODUCT
HYANEB
The patients made a favourable judgement, with statistical significance, on
hypertonic saline serum complemented with hyaluronic acid versus standard
serum, with an average satisfaction opinion score of 4.15 and 3.2, respectively
(P < 0.01).
HSS
HSS

The efficacy of the two hypertonic solutions (Hyaneb and conventional
solution) was comparable, which corroborates the fact that hyaluronic acid
does not modify the osmolality of the 7% sodium chloride solution.
HYANEB has been observed to have a clearly higher tolerability than
conventional hypertonic saline solution, which demonstrates that the
addition of 0.1% hyaluronic acid significantly improves the tolerability
and acceptability of inhaled hypertonic solution, promoting therapeutic
compliance.

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