Serialsjournals.com
I
l of Pharmagenesis
2(1), January-June 2011, pp. 87-97
Formulation Development & Evaluation of Matrix Moderated
Transdermal System of Montelukast Sodium
Upendra Nagaich*1 and Vandana Chaudhary2
1Dept. of Pharmaceutics, B.V.M. College of Pharmacy, Shivpuri Link Road, Gwalior, Madhya Pradesh (India)
2Dept. of Pharmaceutics, Guru Gobind Singh College of Pharmacy, Yamuna Nagar, Haryana (India)
Abstract: The main objective of the present study was to develop the matrix type transdermal films of Montelukast
Sodium and to evaluate them with respect to various
in-vitro and
in-vivo parameters. The matrix type transdermal
systems were prepared by homogeneous dispersion of drug by using different ratios of HPMC K15M & EC
polymers in 8:1, 4:1 and 2:1 ratios were increased to the total weight of 540 mg. HPMC K15M and EC were
dissolved in 15 ml ethanol at room temperature, HPMC K15M as the rate-controlling membrane for all the systems.
The swelling properties of the polymers were studied, and drug-polymer interaction studies were performed.
The patches were subjected to various physicochemical studies,
in-vitro release studies, permeation studies, and
skin irritation studies. The optimized batch of HPMC K15M & EC 8:1 was selected to further study like effect of
different natural permeation enhancers i.e. camphor, menthol and 1,8 cineole. This was done on the basis of
in-
vitro drug release studies. It was found that the batch F1, ratio 8:1 gave the best release rates which were found to
increase with the increase in the concentration of the hydrophilic polymer HPMC K15M. All the patches with
HPMC K15M: EC (8:1) showed controlled and sustained release. Formulation F5 containing 10% camphor was
found to release the highest quantity of drug.
Keywords: Membrane controlled, hydrophilic polymer, swelling ratio, hydrophilic drug,
in-vivo study.
Asthma (GINA) recommend use of anti-
Asthma is the most common chronic disease and inflammatory controller therapy to attenuate
its prevalence has substantially increased long-term inflammation and smooth muscle
worldwide. It is associated with significant dysfunction in persistent asthma, thus preventing
morbidity and economic burden. Chronic permanent airway changes. In this regard, inhaled
inflammation and smooth muscle dysfunction are glucocorticosteroids (ICS) are the recommended
consistent features of asthma pathophysiology. first line controller agents because of their broad
The acute and chronic inflammation in asthma is anti-inflammatory properties. However, for some
the result of extensive infiltration of the airway patients with persistent asthma, ICS fail to achieve
by inflammatory cells including T cells, adequate response without increasing the dose
eosinophils, mast cells and release of (2). These issues led to trials of adding alternative
inflammatory mediators-cytokines and agents like long acting β-2 agonists (LABA),
leukotrienes from these cells (1).
cromolyn sodium and leukotriene modifiers to
achieve optimal disease control research into
Current clinical practice guidelines from asthma pathophysiology enabled to understand
National Asthma Education and Prevention the role of leukotriene as one of the pro-
Programme (NAEPP) and Global Initiative for inflammatory agents in asthma. This initiated
research and development of leukotriene
Corresponding Author:
Upendra Nagaich
modifiers as first mediator specific therapy for
International Journal of Pharmagenesis, 2(1) 2011
Bronchial asthma is associated with coughing, dispersion using different ratios of HPMC K15M
shortness of breath, chest tightness and wheezing. & EC polymers in 8:1, 4:1 and 2:1 ratios were
There is contraction of airway smooth muscle, increased to the total weight of 540 mg. HPMC
mucosal thickening from edema, cellular K15M and EC were dissolved in 15 ml ethanol
infiltration and narrowing of the airway lumen due at room temperature, 50 mg of the drug was
to thick viscid plugs of mucus. The bronchospasm dissolved in solution of HPMC K15M, and EC
in asthma results from the release of various to obtain uniform solution, Dibutyl Pthalate 5%
chemical mediators such as histamine, SRS-A, w/w of dry polymer was used as a plasticizers.
leukotrienes etc. The release of these agents might Backing membrane was cast by pouring and then
occur as a result of antigen-antibody reaction or evaporating 4% aqueous solution of polyvinyl
due to other pathological conditions (4).
alcohol in glass moulds covered on one side with
The concept of delivering drugs through the aluminum foil, at 60 °C for 3 h. The uniform
skin for systemic treatment of disease is gaining dispersion (3 ml each) was cast on the PVA
increasingly great important due to its numerous backing membrane. Now, the polymeric solution
advantages like bypassing hepatic first pass of the drug was poured on to the glass mould
metabolism, enhancement of therapeutic (2.9 cm internal diameter) and dried at room
efficiency, prolonged duration of action of drugs temperature in dust free environment. A release
with short half life and maintenance of steady liner (wax paper) on either side of the film was
plasma level of drug (5).
applied to complete the TDDS. The films were
Treatment of chronic disease like asthma by stored in air tight container at ambient
transdermal route of drug absorption might prove conditions for seven days prior to use, then out
to have several advantages over other routes. of the three polymers combination the best was
Therefore, the objective of the present work is to chosen for the further study by using three
formulate a transdermal film for an anti-asthmatic different natural penetration enhancers Menthol,
drug. Montelukast, which is a cysteinyl-leucotriene 1, 8 Cineole & Camphor. These enhancers were
receptor antagonist, since it has half-life of 2-4 h, used as 5% & 10% (safe concentration)
oral bioavailability, is around 64% (6).
concentration of total weight of the dry polymer.
The dry patches were kept in desiccators until
Therefore, it is one of the most feasible drug use (7, 8).
delivery system for such a drug is transdermal
film for the better management of the disease to
Physical Evaluation
improve patient compliance. Recent years have
witnessed a favorable preference among health
Folding Endurance
care givers for Montelukast, a leukotriene Folding endurance was determined by repeatedly
antagonist in asthma management of children.
folding the film at the same place until it broke.
Materials and Method
The number of times the film could be folded at
the same place without breaking was the folding
Cadila endurance value (9).
Pharmaceuticals, Ahmedabad, HPMC K15M
Zydus Cadila Ahmedabad, India, Ethyl Cellulose
Weight Variation
from Central Drug House (P) Ltd, Camphor from
Karnataka fine chem. Menthol from Mora Weight variation was studied by individually
Industrial Estate, Moradabad, 1,8 Cineole Redox weighing 10 randomly selected films. Such
Pharmachem. Pvt Ltd Haridwar, India. Dibutyl determination was performed for each
Pthalate from Karnataka fine chem. Ethanol: formulation (9).
DCM- Karnataka fine chem.
Film Thickness
Preparation of TDDS Patches
The thickness of films was measured at three
The matrix type transdermal films of Montelukast different places using a Dial caliper and mean
Sodium were prepared by homogeneous values were calculated (9).
Formulation Development & Evaluation of Matrix Moderated Transdermal System of Montelukast.
Determination of Drug Content in the Film
portion of a Wistar rat after killing the animal.
The uniformity of drug distribution was evaluated The hair was removed from the abdominal
by determining drug content of the film by a portion with the help of scissor. The stratum
spectrophotometric method. A known weight of corneum side of the skin was kept in intimate
film was dissolved and diluted subsequently with contact with the release surface of the film under
chloroform and the concentration of Montelukast test placed between the two halves of the
sodium was spectrophotometrically measured at diffusion cell. The receiver phase was filled with
344 nm against the blank chloroform solution simulated phosphate buffer of pH 7.4 stirred at
containing the same amount of polymer and 50 RPM on a magnetic stirrer. The whole
plasticizer without drug (10).
assembly was maintained at 37 ± 0.5 °C. The skin
was first stabilized until no ultraviolet (UV)
Percentage of Moisture Content
absorbance was observed (to eliminate the
The films were weighed individually and kept in possibility of any interference on the permeation
desiccators containing activated silica at room of drug through the skin by ammonia pre-
temperature for 24 h. Individual films were treatment and due to other skin contents). The
weighed repeatedly until they showed a constant amount of drug permeated was determined by
weight. The percentage of moisture content was removing 5 ml samples at appropriate time
calculated as the difference between initial and intervals up to 24 h. The volume was replenished
final weight with respect to final weight (10).
with an equal quantity of pre-warmed receiver
solution. The absorbance was read at 344 nm
Percentage of Moisture Uptake
spectrophotometrically. Cumulative amounts of
drug diffused in mg/cm2 were calculated and
A weighed film kept in desiccators at room plotted against time (11).
temperature for 24 h was taken out and exposed
to 84% relative humidity (a saturated solution of
Skin Irritation Studies
aluminum chloride) in desiccators until a constant
weight for the film was obtained. The percentage The hair on the dorsal side of Wistar rats was
of moisture uptake was calculated as the removed by clipping 1 day before this portion of
difference between final and initial weight with the experiment. The rats were divided into 4
respect to initial weight (10).
groups (n = 3). Group I served as the control,
group II served as optimized formulation OF1,
In-Vitro Drug Release Studies
group III served as optimized formulation OF2
In-vitro drug release studies will be carried out and group IV received a 0.8% v/v aqueous
using U.S.P. dissolution test apparatus II (Paddle solution of formalin as a standard irritant. A new
over Disc method) into simulated phosphate buffer film or new formalin solution was applied daily
of pH 6.8. The transdermal film was mounted on for 7 days. Finally, the application sites were
the disc and placed at the bottom of the dissolution graded according to a visual scoring scale, always
vessel. The dissolution medium was simulated by the same investigator (12).
phosphate buffer of pH 6.8 and the apparatus was
maintained to 37 ± 0.5 °C. The apparatus was
Temperature Dependent Stability Studies
operated at 50 rpm and samples were withdrawn The purpose of stability testing is to provide
at appropriate time intervals up to 24 h and evidence on how the quality of a drug substance
analyzed at 344 nm spectrophotometrically. or drug product varies with time under the
Cumulative % drug released were calculated out influence of a variety of environmental factors
and plotted against time (11).
such as temperature, humidity and light and to
establish a re-test period for the drug substance
Ex-vivo Permeation Studies
or a shelf life for the drug product and
Ex-vivo permeation study was carried out using recommended storage conditions. To assess the
Franz diffusion cell with a diffusion area of 3.14 drug and formulation stability, stability studies
cm2. The skin was removed from the abdominal were done according to ICH guidelines Q1C.
International Journal of Pharmagenesis, 2(1) 2011
Stability studies were carried out on the films different ratios of HPMC K15M to EC (8:1, 4:1
of most satisfactory as per ICH Guidelines Q1C. and 2:1) from batch F1 to F9 as shown in Table
The most satisfactory formulation stored in sealed 1. EC was added to improve the drug release by
in aluminum foil. These were stored at room polymer swelling, elasticity and film forming
temperature for 2 months. Films were evaluated properties of the patches. Butyl phthalate (5%)
for
in-vitro drug release,
ex-vivo permeation study was added as plasticizer. PVA was used for the
and various physical characteristics (13, 14).
casting of backing membrane. On the basis of
physical characteristics and stability studies
most suitable batch was selected for further
Statistical significance of all the data generated studies of penetration enhancers like, Menthol,
was tested by employing ANOVA followed by 1, 8 Cineole & Camphor (5% & 10%
Newman-Keuls compare all pair of columns tests. concentration of total weight of the dry
A confidence limit of P< 0.05 was fixed for polymer).
interpretation of the results using the software
Prepared patches were smooth in appearance,
PRISM (Graph Pad, Version2.01, San Diego, CA). uniform in thickness, mass, and drug content and
Formulation F5 showed significant result when showed no visible cracks. More uniform thickness
compared with all the other formulation (P<0.01). was shown by formulation F1 & F7(0.42 mm). The
maximum folding endurance was shown by F1
formulation HPMC K15M: EC 2:1 which shows
In the present study, Transdermal patches for that in above combination EC is responsible for
controlled delivery of Montelukast Sodium were the strength.
developed using HPMC K15M as the base matrix.
F5 and F6 shows pH resembles that was more
The folding endurance of the prepared patches resembles with skin pH. From physical evaluation
was ranged from 120-125. The average weight F1 formulation compared with all different
varies from 63.9±0.7 (F1) to 88.1± 0.1 (F9). F5 & F6 ranges of penetration enhancers as shown in
shows more uniformity of content of (98.10±0.3, Table 2.
97.10±0.4). The thickness of the prepared patches
Moisture content studies indicated that the
was ranged between 0.35-0.42 mm.
increase in the concentration of hydrophilic
Moisture content of the developed polymer was directly proportional to the increase
formulations F1 to F9 was varied from 2.50.00 to in moisture content of the films. The moisture
4.09.00%. Moisture uptake of the developed content of the prepared formulations was low,
formulations F1 to F9 was varied from 2.20 to which could help the formulations remain stable
and reduce brittleness during long-term storage
as shown in Table 2.
The stability studies showed that the
formulation stored at 5.0 ± 3 ºC, 40 ± 2 °C, 75±5%
Moisture uptake studies indicated that the
RH and room temperature showed percentage increase in the concentration of hydrophilic
cumulative amount of drug per cm2 of patch polymer was directly proportional to the increase
421.06, 418.01 and 416.91 µg respectively in 24 h in moisture uptake of the films. The moisture
after 30 days, 419.80, 412.08 and 409.49.91µg uptake of the formulations was also low, which
respectively in 24 h after 60 days, 407.31, 406.89 could protect the formulations from microbial
and 404.89 µg respectively in 24 h after 90 days contamination and reduce bulkiness as shown in
as shown in Fig. 5, 6, 7.
The optimized batch of HPMC K15M & EC
8:1 was selected to study the effect of different
In the present study, Transdermal patches for natural permeation enhancers i.e. camphor,
controlled delivery of Montelukast Sodium were menthol and 1,8 cineole. This was based on
in-
developed using HPMC K15M as the base
vitro drug release study. It was found that the
matrix. The patches were prepared using batch F9, ratio 8:1 gave the best release rate, which
Formulation Development & Evaluation of Matrix Moderated Transdermal System of Montelukast.
was found to increase with the increasing
The formulation F4 with 5% Camphor was
concentration of the hydrophilic polymer HPMC found; show the best percentage cumulative drug
K15M as shown in Fig. 1.
release of 422.01 mcg/cm2 in 24 h, due to its higher
The
in-vitro skin permeation of Montelukast fluidizing activity among the terpenes containing
sodium from the selected TDDS through depilated essential oils.
goat abdominal skin was conducted using a
Menthol produces local vasodilatation and
modified Keshery-Chein diffusion cell. Percent could distribute preferentially into the
cumulative amounts of drug permeated cm2 of intercellular spaces of stratum corneum and the
patches were analyzed spectrophotometrically at possible reversible disruption of the intercellular
344 nm as shown in Table 3.
lipid domain (16) and 1,8 cineole improved the
All the patches with HPMC K15M: EC (8:1) skin permeation of hydrophilic drugs better than
showed controlled and sustained release. other terpenes and Montelukast sodium is
Formulation F4 containing 5% camphor was hydrophobic in nature (17). Menthol was the most
found to release the highest quantity of drug, effective permeation enhancer than the 1, 8
422.01 µg/cm2 of drug in 24 h as shown in Fig. 2. cineole.
All the formulations with and without
Transdermal flux for different Montelukast
permeation enhancers, F1 (without permeation sodium formulations with natural permeation
enhancer), F4 and F5 (camphor- 5%, 10%) as enhancers depilated mouse abdominal skin was
shown in Fig. 2, F6 and F7 (menthol 5%, 10%) as conducted using a modified Keshary-chein
shown Fig. 3, F8 and F9 (1, 8 cineole 5%, 10%) as diffusion cell Table 3. The flux from drug-polymer
shown Fig. 4, appeared to follow similar patterns TDDS (without permeation enhancer) was less
of drug release profiles, i.e. initially apparent zero- release of drug than that obtained after
order and then first order release kinetics. Initially application of camphor, menthol, 1,8 cineole. The
for first few hours the drug release, kinetic scanning electron microscopy (SEM) is carried out
patterns followed zero-order drug release profiles for formulation F5 as shown in Fig. 8, 9, 10, 11.
and with the enhancement of time the release
The data indicated that the transdermal flux
profiles gradually changed into the concentration of Montelukast sodium increased with presence
dependent first order release kinetics as shown of 5% of camphor than comparison of other
penetration enhancer in the formulation. Hence
The effect of permeation enhancers often Camphor is better permeation enhancer than
depends on their applied concentrations (11). menthol and 1,8 cineole as shown in Fig. 12.
The mechanism of action of permeation
Formulation F4 subjected to stability studies
enhancers (7) are-: (i) disruption of the highly was stored at 5 ± 3 ºC, room temperature and 40
ordered structure of SC lipids, (ii) interactions ± 2ºC, 75% RH for three months. Optimal storage
with intracellular proteins or (iii) improvement conditions of the formulation were assayed by
in partitioning of the drug, co-enhancers or co- analyzing the percentage cumulative amount of
solvent into the stratum corneum. From the drug permeated per cm2 of patch after time
studies it was reported that terpenes enhance interval of 30, 60, 90 days. It was determined
diffusion of drugs by extracting lipids from by plotting graph between percentage
stratum corneum (14, 15) which results in cumulative amount of drug per cm2 of patch and
reorganization of lipid domain and barrier time intervals that reflected kinetics of release
disruption (16, 17). The mechanism of barrier profile.
disruption may be due to the competitive
hydrogen bonding of oxygen containing
The percentage cumulative amount of drug
monoterpenes with ceramide head groups, from the formulation stored at 2–8ºC was found
thereby breaking the interlamellar hydrogen- higher in comparison with the formulation stored
bonding network of lipid bilayer of stratum at room temperature, and 40 ± 2ºC, This indicated
corneum and new polar pathways or channels that the formulation tend to degrade faster at
are formed (17).
higher temperature.
International Journal of Pharmagenesis, 2(1) 2011
Composition of Prepared Films
Different Combination of HPMC K15m: Ec
ETHANOL: DCM (1:1)
Surface pH
*All values are expressed as mean ± SD (n = 6)
In- vitro Skin Permeation Profile of HPMC K15M: EC Patches
Cumulative Drug Release(mcg/sq.cm2)
*Significant compared with all other formulation (P < 0.01).
Formulation Development & Evaluation of Matrix Moderated Transdermal System of Montelukast.
Permeation Kinetic Studies of Various Batches
Kinetic Profile
For Higuchi
For Pappas
For 1st order Equation
For Zero Order
of formulations
Stability Studies Physical Characteristic of Best Formulation F4 during Stability Studies
endurance
Room temperature 20±2
Room temperature 21±3
Room temperature 20±3
Figure 1: Plot of Cumulative Drug Release Vs Time Profile
International Journal of Pharmagenesis, 2(1) 2011
Figure 2: Skin Permeation Studies of HPMC K15M & EC (F-9, 8:1) Combinations with 5% Camphor as Permeation Enhancer
Figure 3: Skin Permeation Studies of HPMC K15M & EC Combinations with Menthol as Permeation Enhancer
Figure 4: Skin Permeation Studies of HPMC K15M & EC Combinations with 1,8 Cineole as Permeation Enhancer
Formulation Development & Evaluation of Matrix Moderated Transdermal System of Montelukast.
Figure 5: % Cumulative Amount Release Profile of Formulation F5 during Stability Studies
Figure 6: % Cumulative Amount Release Profile of Formulation F5 during Stability Studies
Figure 7: % Cumulative Amount Release Profile of Formulation F5 during Stability Studies
International Journal of Pharmagenesis, 2(1) 2011
Figure 8: Scanning Electron Microscopy of Normal F5 Film Figure 11:Scanning Electron Microscopy of F5 Film after 8
at X300 Magnification
h skin Permeation at X1000 Magnification
Figure 9: Scanning Electron Microscopy of Normal F5 Film
at X1000 Magnification
Figure 12:In-vitro Skin Permeation Studies
Conclusion
In the present study, an attempt was made to
develop unidirectional transdermal films of
Montelukast sodium for treatment/management
of asthma. Montelukast sodium transdermal
delivery system prepared by matrix diffusion
Figure 10:Scanning Electron Microscopy of F5 Film after 8
type technique with different range of compatible
h skin Permeation at X300 Magnifications
polymers like HPMC K15M as a rate controlling
Formulation Development & Evaluation of Matrix Moderated Transdermal System of Montelukast.
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The International Journal of Biochemistry & Cell Biology 38 (2006) 1975–1985 Co-expression of chaperonin GroEL/GroES enhances in vivo folding of yeast mitochondrial aconitase and alters the growth characteristics of Escherichia coli Parul Gupta, Nishtha Aggarwal, Pragya Batra, Saroj Mishra, Tapan K. Chaudhuri Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology, Delhi,
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