Extemporaneous Topical Minoxidil Solutions for the Treatment of Alopecia: Stability Studies and Incorporation Tests of Active Ingredients in ALOPLUS FAST Base.

Minoxidil is a vasodilator drug generally employed for the treatment of various forms of alopecia. In this article, the authors propose an alternative to the formulation reported in the British Pharmacopoeia for the realization of topical minoxidil -based solutions using ALOPLUS FAST. This liquid vehicle is an ethanol- and propylene glycol-free base which allows the complete solubilization of minoxidil, thanks to the presence of hydroxypropyl-ß-cyclodextrin. Solubility and chemical stability studies of the active ingredient in the formulation at a concentration of 5% w/w and physical stability studies of this extemporaneous preparation are reported. Incorporation tests of various active pharmaceutical ingredients that can be combined with minoxidil for alopecia synergic treatment have been carried out. Analyses were performed by using a high-pressure liquid chromatography analytical method. The results showed that the intrinsic solubility of the drug in the liquid base was 62.37 mg/mL ± 0.85 mg/mL (5.24 w/w ± 0.07% w/w) at 25°C; minoxidil was chemically stable in ALOPLUS FAST; and the formulation was physically stable for more than six months, under different storage conditions. Incorporation tests of several active pharmaceutical ingredients in 2% to 4% w/w minoxidil formulations were successful as well.

Estimation of minoxidil in human plasma using UHPLC-MS/MS and its application in pharmacokinetic study.

Measurement of drug concentration in biological matrices (such as serum, plasma, blood, urine, and saliva) is important to determine Bioavailability (BA) and/or Bioequivalence (BE) of a drug product which are required during the drug product development and approval process to support applications for new active substances (INDs, NDAs) and generic (ANDAs) drug products to make critical decisions on safety and efficacy. Because of their vital role, bioanalytical methods should be well-characterized, fully validated and documented to yield reliable results. In present work, a simple, specific, high throughput, accurate and sensitive UHPLC-MS/MS method has been developed and validated for quantification of Minoxidil in human plasma. The analyte and the internal standard were extracted from plasma by Liquid-Liquid Extraction using ethyl acetate. The chromatographic separation was achieved on Thermo Hypersil Gold column (4.6x50mm, 5µm) using acetonitrile-0.1% formic acid in water (60:40, v/v) at a flow rate of 0.400 ml/min. Detection by turbospray positive ionization mass spectrometry in the multiple reaction monitoring mode with a mass transition ion-pair of m/z 210.152 → 163.965 (Minoxidil) and m/z 220.267 → 169.089 (Internal Standard-Minoxidil D10) was found to be linear over the concentration range of 1.280 to 151.075 ng/ml. The method was fully validated as per USFDA guidelines and the results were within regulatory limits. The inter and intra-day precision ranged from 5.42 to 9.27% and 2.55-9.42% respectively. The inter and intra-day accuracy ranged from 89.2 to 98.9% and 102-105% respectively. The method was successfully applied to a BE study involving human volunteers.

Colored Polymeric Nanofiber Loaded with Minoxidil Sulphate as Beauty Coverage and Restoring Hair Loss.

Polymeric nanofibers fabricated by electrospinning either blank (PVA) or loaded with minoxidil sulphate have yielded optimum fibers with an average diameter 273 nm, and 511 nm, respectively. Thermal analysis of nanofibers indicated no chemical interaction. The NMR spectrum confirmed stability of nanofiber as there were no interactions between functional groups. Prepared nanofibers showed a 47.4% encapsulation efficiency and 73% yield. In vitro drug release of minoxidil sulphate from nanofiber exhibited an initial burst release followed by a slower release pattern. Stability studies revealed that minoxidil nanofiber was stable if stored at room temperature and protected from light with only loss of 9.6% of its nominal concentration within 6 months. As a result, the prepared solid/colored formula serves as an ideal formulation for such instable drug in liquid formula taking the advantage of the attractiveness of beauty colored coverage, and the simple, and non-tousled application.

Exploring the potential of minoxidil tretinoin liposomal based hydrogel for topical delivery in the treatment of androgenic alopecia.

Purpose: Androgenic alopecia (AGA) is a condition of progressive hair loss and involves follicular miniaturization triggered mainly due to varying levels of androgen besides environmental and genetic factors, which may also play some role. Minoxidil (MXD) has been considered as most effective therapeutic moiety to treat this disorder. Another drug Tretinoin (TRET) is known for its comedolytic activity and is reported to enhance percutaneous absorption of MXD. Presently both these drugs are being utilized for treatment of androgenic alopecia (AGA) in solution form which poses several problems in terms of poor solubility of drug, frequency of application and side effects.Materials and methods: Current work investigates liposomal hydrogel system for simultaneous delivery of MXD and TRET to overcome the limitations of existing formulation. Successful development of liposomes was commenced by thin film hydration method and various parameters affecting desired characteristics like size, morphology, entrapment efficiency; stability and ex vivo permeation were optimized. The formulated liposomes were further characterized for various physicochemical properties and evaluated for in vivo irritancy study in animals.Results and discussion: Results suggested prepared liposomes to be stable, homogenous and capable to hold both the drugs within. Association with hydrogel enhanced the permeation of MXD through skin ex vivo but TRET retained on the skin. Liposome loaded hydrogel was found to be non-irritant to skin.Conclusion: Overall developed system showed potential for effective and simultaneous delivery of both the drugs.

Minoxidil and its use in hair disorders: a review.

Minoxidil was first introduced as an antihypertensive medication and the discovery of its common adverse event, hypertrichosis, led to the development of a topical formulation for promoting hair growth. To date, topical minoxidil is the mainstay treatment for androgenetic alopecia and is used as an off-label treatment for other hair loss conditions. Despite its widespread application, the exact mechanism of action of minoxidil is still not fully understood. In this article, we aim to review and update current information on the pharmacology, mechanism of action, clinical efficacy, and adverse events of topical minoxidil.

The use of minoxidil in the treatment of male and female androgenetic alopecia: a story of more than 30 years.

Even if minoxidil has been known for over 30 years as "hair growth stimulator" the precise mechanism of its action is not completely elucitated. Minoxidil shortens telogen, accelerates telogen-exogen phase and causes the premature entry of resting hair follicles into anagen phase. Moreover, minoxidil increases hair follicle size. A large part of hair treatment scientific literature confirms the efficacy of topically applied minoxidil in humans. In particular, patients treated with minoxidil showed a significant increase in "non vellus" hair count starting from baseline. Preparation of minoxidil requires molecule stability and solubility. Today are available on the market minoxidil-based formulations having low-concentration of propylene glycol to obtain preparations with a better cosmetical acceptance and dermatological safety. The body of evidences indicates that minoxidil still represent a milestone in the treatment of androgenetic alopecia and that its story is going on.

Alginate-Based Hydrogel Containing Minoxidil/Hydroxypropyl-ß-Cyclodextrin Inclusion Complex for Topical Alopecia Treatment.

Cutaneous minoxidil (MXD) formulations were developed with the intent to reduce the side effects of the cosolvents propylene glycol and ethanol, frequently used in commercial MXD solutions. Completely aqueous alginate-based hydrogels were investigated and MXD aqueous solubility was improved using inclusion complexes with hydroxypropyl-ß-cyclodextrin (HP-ß-CD) at 2 different molar substitution degree (MS), namely 0.65 and 0.85. HP-ß-CD MS 0.65 was selected for its improved solubilizing ability toward MXD. At concentration of 39% w/v, this cyclodextrin increased the intrinsic aqueous solubility of MXD of about 22-fold. The calculated complexation constant was 2309 ± 20 M-1, and the inclusion process was spontaneous and enthalpically driven. Nuclear magnetic resonance studies (Job plot, 1H, 2D correlations spectroscopy, nuclear overhauser effect spectroscopy, and rotating-frame overhauser enhancement spectroscopy) confirmed the stoichiometry 1:1 between MXD and HP-ß-CD providing information about the exact geometry of the inclusion complex. Rheological and in vitro release studies performed on the formulation loaded with MXD 3.5% w/w proved that the inclusion complex increased the viscosity of the hydrogel modulating the release of the free drug. Furthermore, the hydrogel formulation facilitate MXD to permeate into the skin and did not damage epidermis, suggesting that these completely aqueous MXD delivery systems can be proposed as alternative formulations to commercial solutions.

Isolation and structural identification of a novel minoxidil analogue in an illegal dietary supplement: triaminodil.

A new minoxidil analogue was detected in an illegal dietary supplement advertised as a hair-growth treatment. The analogue was identified using ultra-performance liquid chromatography (UPLC), high-resolution mass spectrometry (LC-HR-MS) and nuclear magnetic resonance (NMR) spectroscopy. The compound was structurally elucidated as a minoxidil analogue in which the piperidinyl group of minoxidil was replaced with a pyrrolidinyl group corresponding to a molecular formula of C8H13N5O. The new analogue has been named triaminodil. As this is the first report of the compound, there are no chemical, toxicology or pharmacological data available.

Characterization of minoxidil/hydroxypropyl-ß-cyclodextrin inclusion complex in aqueous alginate gel useful for alopecia management: Efficacy evaluation in male rat.

Solid inclusion complex between hydroxypropyl-ß-cyclodextrin (HP-ß-CD) and minoxidil (MXD) was prepared by freeze-drying and characterized by yield, drug loading and dissolution rate. Moreover, the complex was formulated as alginate gel (GEL HP-ß-CD)/MXD 3.5% w/w). The efficacy of the novel GEL HP-ß-CD)/MXD 3.5% w/w and of MXD 3.5% w/w ethanolic/propylene-glycol solution (MXD solution) were evaluated by monitoring the hair growth of dorsal skin 1-4 weeks after depilation followed by histological analysis and gene expression in skin biopsies in male rat. Patch-clamp experiments and cell-dehydrogenase activity (CDA) were performed to evaluate the capability of the formulations to activate "in vitro" the ATP-sensitive K+-channels (KATP) and their effects on cell viability in skin fibroblasts. After 3 weeks, the MXD solution and MXD/HP-ß-CD GEL enhanced the hair growth, respectively, of 80.1 ±â€¯2% and 84.3 ±â€¯4% vs controls. After 4 weeks, the MXD/HP-ß-CD GEL significantly enhanced the hair length and bulb diameter vs others groups. The MXD/HP-ß-CD GEL significantly enhanced the mRNA levels of the SUR2 and Kir6.1 subunits of the KATP channels and AKT2 vs other groups. The AR gene was down-regulated vs controls following the treatment with either MXD formulations. Either MXD (10-4 M) formulations were effective in potentiating the KATP currents. The MXD solution and its vehicle after 9 h of incubation time, but not MXD/HP-ß-CD, reduced CDA in fibroblasts. In sum, the MXD/HP-ß-CD GEL shows a favorable profile following topical long-term use.

Interactions and release of two palmitoyl peptides from phytantriol cubosomes.

Phytantriol cubosomes loaded with two palmitoyl peptides (Palpepcubes), namely GHKcube and GQPRcube, were prepared using an ultrasonication protocol. The Palpepcubes dimensions were characterized by dynamic light scattering (DLS) and cryo-transmission electron microscopy (cryo-TEM). Small-angle X-ray scattering (SAXS) analyses revealed that the bicontinuous cubic structure remained even at palmitoyl peptide contents as high as 5wt.%, with an increase in the cell parameter from approximately 6.5 to 7.2nm. Isothermal titration calorimetry (ITC) was used to elucidate the interactions between the blank cubosomes and the palmitoyl peptides, revealing an exothermic process of interaction. Moreover, the in vitro release of the palmitoyl peptides from the Palpepcubes was studied using a dialysis method coupled with liquid chromatography-mass spectrometry (LC/MS) technique, in which a sustained release of up to a few days was observed. Finally, the stability of the aqueous solutions of the palmitoyl peptides and the Palpepcubes kept at room temperature and at low temperature (4°C) was studied by LC/MS method, indicating that incorporation into cubosomes increases the peptide stability significantly.

Structural characterization and dissolution profile of mycophenolic acid cocrystals.

Three novel cocrystals of mycophenolic acid (MPA) with isonicotinamide (MPA-ISO), minoxidil (MPA-MIN) and 2,2'-dipyridylamine (MPA-DPA) as coformers have been prepared successfully by both slow evaporation and liquid-assisted grinding. The structures of these cocrystals show that all the three coformers form hydrogen bonds with the carboxylic acid group of MPA. The cocrystal MPA-ISO possesses remarkably improved solubility and dissolution rate, while two other cocrystals exhibit the opposite characteristics. The solids in the slurry with pH6.8 phosphate buffer and cocrystals remain as the incipient cocrystal after 24h. However, evidence of slight polymerization was shown in the slurry of pH6.8 phosphate buffer with MPA and MPA-ISO cocrystal.

Preparation and Characterization of Minoxidil Loaded Nanostructured Lipid Carriers.

Nanostructured lipid carriers (NLCs) are interesting delivery systems for enhancing the penetration of an active substance through the skin after topical administration. The present paper described the development of a novel NLCs for minoxidil (MXD) topical delivery. Stearic acid and oleic acid that showed the highest solubility for MXD were selected as solid lipid and liquid lipid, respectively, and the NLCs were prepared by hot high pressure homogenization method. The minoxidil loaded NLCs prepared accordingly to the optimal formulation exhibited spherical shape with a mean diameter of 281.4 ± 7.4 nm, polydispersity of 0.207 ± 0.009, zeta potential of -32.90 ± 1.23 mV, drug entrapment efficiency of 92.48 ± 0.31%, and drug loading of 13.85 ± 0.47%. Storage stability studies demonstrated that the particle size and entrapment efficiency of the MXD-NLCs were not changed during 3 months both at 4°C and room temperature. Moreover, the release of MXD from the NLCs was faster than drug release from SLNs. In vitro skin permeability test demonstrated that MXD-NLCs had a more pronounced permeation and retention profile than MXD-SLNs. Furthermore, no erythema was observed after administration of MXD-NLCs. All these results indicated that the developed MXD-NLCs could be a promising and effective nanocarrier for topical delivery of MXD.

Solid effervescent formulations as new approach for topical minoxidil delivery.

Currently marketed minoxidil formulations present inconveniences that range from a grease hard aspect they leave on the hair to more serious adverse reactions as scalp dryness and irritation. In this paper we propose a novel approach for minoxidil sulphate (MXS) delivery based on a solid effervescent formulation. The aim was to investigate whether the particle mechanical movement triggered by effervescence would lead to higher follicle accumulation. Preformulation studies using thermal, spectroscopic and morphological analysis demonstrated the compatibility between effervescent salts and the drug. The effervescent formulation demonstrated a 2.7-fold increase on MXS accumulation into hair follicles casts compared to the MXS solution (22.0±9.7µg/cm2 versus 8.3±4.0µg/cm2) and a significant drug increase (around 4-fold) in remaining skin (97.1±29.2µg/cm2) compared to the drug solution (23.5±6.1µg/cm2). The effervescent formulations demonstrated a prominent increase of drug permeation highly dependent on the effervescent mixture concentration in the formulation, confirming the hypothesis of effervescent reaction favoring drug penetration. Clinically, therapy effectiveness could be improved, increasing the administration interval, hence, patient compliance. More studies to investigate the follicular targeting potential and safety of new formulations are needed.

A Phase III, Multicenter, Parallel-Design Clinical Trial to Compare the Efficacy and Safety of 5% Minoxidil Foam Versus Vehicle in Women With Female Pattern Hair Loss.

UNLABELLED: BACKGROUND Female pattern hair loss (FPHL) is a common hair disorder that affects millions of women. A new 5% minoxidil topical foam (MTF) formulation, which does not contain propylene glycol, has been developed.
OBJECTIVE: To compare the efficacy and safety of once-daily 5% MTF with vehicle foam for the treatment of FPHL.
MATERIALS AND METHODS: This was a Phase III, randomized, double-blind, vehicle-controlled, parallel-group, international multicenter trial (17 sites) in women aged at least 18 years with FPHL (grade D3 to D6 on the Savin Density Scale), treated once daily with 5% MTF or vehicle foam for 24 weeks. The co-primary efficacy endpoints were the change from baseline at week 24 in target area hair count (TAHC) and subject assessment of scalp coverage. Also evaluated were TAHC at week 12, expert panel review of hair regrowth at week 24, and change from baseline in total unit area density (TUAD, sum of hair diameters/cm2) at weeks 12 and 24.
RESULTS: A total of 404 women were enrolled. At 12 and 24 weeks, 5% MTF treatment resulted in regrowth of 10.9 hairs/cm2 and 9.1 hairs/cm2 more than vehicle foam, respectively (both P<.0001). Improved scalp coverage at week 24 was observed by both subject self-assessment (0.69-point improvement over vehicle foam; P<.0001) and expert panel review (0.36-point improvement over the vehicle foam; P<.0001). TUAD increased by 658 μm/cm2 and 644 μm/cm2 more with 5% MTF than with vehicle foam at weeks 12 and 24, respectively (both P<.0001). MTF was well tolerated. A low incidence of scalp irritation and facial hypertrichosis was observed, with no clinically significant differences between groups.
CONCLUSION: Five percent MTF once daily for 24 weeks was well tolerated and promoted hair regrowth in women with FPHL, resulting in improved scalp coverage and increased hair density compared with vehicle foam. ClinicalTrials.gov identifier: nCT01226459

J Drugs Dermatol. 2016;15(7):874-881.

Efficacy and Safety of Once-Daily Minoxidil Foam 5% Versus Twice-Daily Minoxidil Solution 2% in Female Pattern Hair Loss: A Phase III, Randomized, Investigator-Blinded Study.

BACKGROUND: A once-daily minoxidil topical foam (MTF) has been developed to treat female pattern hair loss.
OBJECTIVE: Determine noninferiority of once-daily 5% MTF versus twice-daily 2% minoxidil topical solution (MTS) based on the change from baseline in target area hair count (TAHC) at 24 weeks. METHODS: In a randomized, phase III trial, women with female pattern hair loss received once-daily 5% MTF (n=161) or twice-daily 2% MTS (n=161) for 52 weeks. Primary endpoint was change from baseline in TAHC at 24 weeks. Secondary endpoint was change from baseline in TAHC at 12 weeks. Exploratory endpoints included change in total unit area density and change in overall scalp coverage.
RESULTS: Once-daily 5% MTF increased TAHC from baseline (adjusted mean ± standard error) by 23.9 ± 2.1 hairs/cm2 at week 24. Twice-daily 2% MTS increased TAHC 24.2 ± 2.1 hairs/cm2 at week 24. The treatment difference was -0.3 hairs/cm2 (95% CI = -6.0, 5.4). Since the lower bound of the 95% CI was less than -5.0, the prespecified noninferiority goal was not met. Both treatments were well tolerated.
CONCLUSIONS: Once-daily 5% MTF and twice-daily 2% MTS induced hair regrowth in female pattern hair loss, but prespecified noninferiority criteria were not met.
ClinicalTrials.gov identifier: NCT01145625

J Drugs Dermatol. 2016;15(7):883-889.

Minoxidil topical treatment may be more efficient if applied on damp scalp in comparison with dry scalp.

There is yet no consensus among prescribers whether minoxidil (MXD) formulations should be applied on wet/damp or dry scalp and no clear FDA guidelines on the matter. We hypothesized that the use of MXD on damp scalp may lead to higher drug penetration. First, because the drug diffusion and consequent deposition into the hair follicle may be favored when follicle cast is humid. Second, because humidity may also prevent drug crystallization and, therefore, maintain a higher thermodynamic activity for longer periods, which leads to increased penetration. Following in vitro experiments on rat and porcine skin we confirmed the hypothesis, which could markedly improve treatment effectiveness.

Efficacy and Safety of Minoxidil 2% Solution in Combination With a Botanical Hair Solution in Women With Female Pattern Hair Loss/Androgenic Alopecia.

Female pattern hair loss (FPHL), also known as female androgenic alopecia, affects over 21 million women in the United States with devastating effects on self-esteem and psychosocial functioning. Topical minoxidil 2% and 5% formulations are the only US Food and Drug Administration-approved treatments for FPHL. The length of time it typically takes to observe the benefits is a challenge for many patients, and may affect adherence to treatment. Herbal extracts, which are also believed to promote healthier-looking hair, have a long history of use in hair care formulations. The safety and efficacy of a twice-daily regimen of 2% minoxidil solution used in combination with the botanical hair solution for 12 weeks in 54 subjects was evaluated in a multicenter, single-arm, open-label study. Assessments included investigator and subject ratings of improvement and subject satisfaction. Investigator ratings indicated significant improvement in hair growth and overall treatment benefits in as early as 6 weeks (P<.001). Subject self-ratings indicated significant satisfaction with hair volume and quality improvement at week 6 (P<.001). Subjects also indicated an increase in self-confidence and attractiveness at week 12 (P<.001). The investigator and subject-assessed efficacy and subject satisfaction with this regimen provides clinicians with an effective treatment option for FPHL that also provides a high level of patient acceptance, which ultimately may help promote minoxidil treatment adherence.

Efficacy and Safety of Minoxidil 5% Foam in Combination With a Botanical Hair Solution in Men With Androgenic Alopecia.

Androgenic alopecia (AGA) is the most common type of hair loss in men, characterized by hair miniaturization, hairline recession, and vertex balding. It affects approximately 50% of men, negatively affecting self-esteem and sociability. Topical minoxidil formulations are approved up to a 5% concentration for men, but patient adherence to treatment is challenged by gradual results that may be perceived as a lack of initial benefit. Herbal extracts, which are also believed to promote healthier-looking hair, have a long history of use in hair care formulations. The safety and efficacy of a twice-daily regimen of 5% minoxidil foam used in combination with a novel botanical hair solution was evaluated in a 12-week, multicenter, single-arm, open label study in 56 subjects with mild to moderate AGA. Assessments included investigator ratings of improvement and subject self-ratings of satisfaction. Investigator ratings indicated significant improvement in scalp hair coverage and perception of overall treatment benefit in as early as 4 weeks (P<.001). Subject self-ratings were significant for improved hair growth and hair appearance in as few as 4 weeks (P<.05). The regimen was well tolerated, and subjects indicated a high degree of satisfaction. Investigator and subject-assessed efficacy and subject satisfaction with this novel regimen provide clinicians with an effective treatment option for AGA that also provides a high level of patient satisfaction, which may help promote patient adherence to long-term treatment.

Synthesis of minoxidil conjugates and their evaluation as HL-60 differentiation agents.

Activation of minoxidil (MNX) with N,N'-carbonyldiimidazole and coupling with natural polyamines (PAs) and commercially available aliphatic or aromatic amines provided a series of new conjugates which were evaluated for their ability to induce differentiation to HL-60 acute myeloid leukemia cancer cells, using a modified NBTZ reduction test. Although neither MNX nor 4,4'-methylenedianiline (MDA) or 2,7-diaminofluorene (DAF), alone or in combination, had any effect, the MNX-spermine (SPM) conjugate (11) and the conjugates 7 and 8 of MNX with MDA and DAF exhibited a differentiation-inducing effect at a concentration of 10 µM without being toxic on proliferating human peripheral blood mononuclear cells.