Efficacy of ADAM Zolmitriptan for the Acute Treatment of Difficult-to-Treat Migraine Headaches

Advancements in microneedle fabrication techniques: artificial intelligence assisted 3D-printing technology

Microneedles (MNs) are micron-scale needles that are a painless alternative to injections for delivering drugs through the skin. MNs find applications as biosensing devices and could serve as real-time diagnosis tools. There have been numerous fabrication techniques employed for producing quality MN-based systems, prominent among them is the three-dimensional (3D) printing. 3D printing enables the production of quality MNs of tuneable characteristics using a variety of materials. Further, the possible integration of artificial intelligence (AI) tools such as machine learning (ML) and deep learning (DL) with 3D printing makes it an indispensable tool for fabricating microneedles. Provided that these AI tools can be trained and act with minimal human intervention to control the quality of products produced, there is also a possibility of mass production of MNs using these tools in the future. This work reviews the specific role of AI in the 3D printing of MN-based devices discussing the use of AI in predicting drug release patterns, its role as a quality control tool, and in predicting the biomarker levels. Additionally, the autonomous 3D printing of microneedles using an integrated system of the internet of things (IoT) and machine learning (ML) is discussed in brief. Different categories of machine learning including supervised learning, semi-supervised learning, unsupervised learning, and reinforced learning have been discussed in brief. Lastly, a brief section is dedicated to the biosensing applications of MN-based devices.

Prediction of drug permeation through microneedled skin by machine learning

Stratum corneum is the outermost layer of the skin preventing external substances from entering human body. Microneedles (MNs) are sharp protrusions of a few hundred microns in length, which can penetrate the stratum corneum to facilitate drug permeation through skin. To determine the amount of drug delivered through skin, in vitro drug permeation testing is commonly used, but the testing is costly and time-consuming. To address this issue, machine learning methods were employed to predict drug permeation through the skin, circumventing the need of conducting skin permeation experiments. By comparing the experimental data and simulated results, it was found extreme gradient boosting (XGBoost) was the best among the four simulation methods. It was also found that drug loading, permeation time, and MN surface area were critical parameters in the models. In conclusion, machine learning is useful to predict drug permeation profiles for MN-facilitated transdermal drug delivery.

Exploring user and stakeholder perspectives from South Africa and Uganda to refine microarray patch development for HIV PrEP delivery and as a multipurpose prevention technology

BACKGROUND

Oral HIV pre-exposure prophylaxis (PrEP) is highly effective, but alternative delivery options are needed to reach more users. Microarray patches (MAPs), a novel drug-delivery system containing micron-scale projections or "microneedles" that deliver drugs via skin, are being developed to deliver long-acting HIV PrEP and as a multipurpose prevention technology to protect from HIV and unintended pregnancy. We explored whether MAP technology could meet user and health system needs in two African countries.

METHODS

Researchers in South Africa and Uganda conducted 27 focus group discussions, 76 mock-use exercises, and 31 key informant interviews to explore perceptions about MAPs and specific features such as MAP size, duration of protection, delivery indicator, and health system fit. Participants included young women and men from key populations and vulnerable groups at high risk of HIV and/or unintended pregnancy, including adolescent girls and young women; female sex workers and men who have sex with these women; and men who have sex with men. In Uganda, researchers also recruited young women and men from universities and the community as vulnerable groups. Key stakeholders included health care providers, sexual and reproductive health experts, policymakers, and youth activists. Qualitative data were transcribed, translated, coded, and analyzed to explore perspectives and preferences about MAPs. Survey responses after mock-use in Uganda were tabulated to assess satisfaction with MAP features and highlight areas for additional refinement.

RESULTS

All groups expressed interest in MAP technology, reporting perceived advantages over other methods. Most participants preferred the smallest MAP size for ease of use and discreetness. Some would accept a larger MAP if it provided longer protection. Most preferred a protection duration of 1 to 3 months or longer; others preferred 1-week protection. Upper arm and thigh were the most preferred application sites. Up to 30 minutes of wear time was considered acceptable; some wanted longer to ensure the drug was fully delivered. Self-administration was valued by all groups; most preferred initial training by a provider.

CONCLUSIONS

Potential users and stakeholders showed strong interest in/acceptance of MAP technology, and their feedback identified key improvements for MAP design. If a MAP containing a high-potency antiretroviral or a MAP containing both an antiretroviral and hormonal contraceptive is developed, these products could improve acceptability/uptake of protection options in sub-Saharan Africa.

Microneedle-enabled therapeutics delivery and biosensing in clinical trials

Microneedles (MNs) are micron-sized protrusions attached to a range of devices that are used in therapeutic delivery and diagnosis. Because MNs can be self-applied, are painless, and can carry multiple therapeutic agents, they have received extensive attention, and have been widely investigated, for local and systemic therapy. Many researchers are currently working to extend the use of MNs to clinical applications. In this review, we provide an update and analysis on MN-based clinical trials since their inception in 2007. The MNs in clinical trials are classified into five types based on their appearance and properties, including: hollow MNs, MN patches, radiofrequency MNs, MN rollers, and other MNs. The various aspects of MN trials are summarized, such as MN types, clinical trial time, and trial regions. This review aims to present an overview of MN development and provide insights for future research in this field. To our knowledge, this is the first review focused on MN clinical trials which showcases the latest applications of this advanced technology in medicine.

Core-shell microneedle patch for six-month controlled-release contraceptive delivery

There is a tremendous need for simple-to-administer, long-acting contraception, which can increase access to improved family planning. Microneedle (MN) patches enable simple self-administration and have previously been formulated for 1-2 months' controlled release of contraceptive hormone using monolithic polymer/drug MN designs having first-order release kinetics. To achieve zero-order release, we developed a novel core-shell MN patch where the shell acts as a rate-controlling membrane to delay release of a contraceptive hormone, levonorgestrel (LNG), for 6 months. In this approach, LNG was encapsulated in a poly(lactide-co-glycolide) (PLGA) core surrounded by a poly(l-lactide) (PLLA) shell and a poly(D,l-lactide) (PLA) cap that were fabricated by sequential casting into a MN mold. Upon application to skin, the core-shell MNs utilized an effervescent interface to separate from the patch backing within 1 min. The core-shell design limited the initial 24 h burst release of LNG to 5.8 ± 0.5% and achieved roughly zero-order LNG release for 6.2 ± 0.1 months in vitro. A monolithic MN patch formulated with the same LNG and PLGA core, but without the rate-controlling PLLA shell and PLA cap had a larger LNG burst release of 22.6 ± 2.0% and achieved LNG release for just 2.1 ± 0.2 months. This study provides the first core-shell MN patch for controlled months-long drug release and supports the development of long-acting contraception using a simple-to-administer, twice-per-year MN patch.

Microneedle patch designs to increase dose administered to human subjects

Microneedle (MN) patches are being developed for many different kinds of drugs, but are often limited to delivering sub-milligram doses. This is because larger patches can be more difficult to apply to the skin, and acceptability of larger MN patches by human subjects has received limited study. Here, we fabricated 18 different large MN patch designs by laser microfabrication with different MN length (800-1500 μm), number of MNs (225 to 900 MNs per patch), space between MNs (600-1100 μm), and MN base diameter (200-250 μm). After manual application of these patches to human participants, we assessed dose delivery efficiency, total dose delivered, dose delivered per MN, depth of MN penetration and whole-MN delivery efficiency. We found that all of these parameters generally increased with decreased MN length, increased number of MNs (among those ≤1000 μm in length) and increased MN-MN spacing. All MN patch designs caused less pain than a pin prick sensation and were generally considered acceptable by the study participants. The MN patches induced mild, or sometimes moderate, transient erythema on skin. Study participants showed higher preference for MN patches for long-acting contraception compared with conventional options, indicating strong interest and acceptability of MN patches in this study.

Administration of pilocarpine by microneedle patch as a novel method for cystic fibrosis sweat testing

The sweat test is the gold standard for the diagnosis of cystic fibrosis (CF). The test utilizes iontophoresis to administer pilocarpine to the skin to induce sweating for measurement of chloride concentration in sweat. However, the sweat test procedure needs to be conducted in an accredited lab with dedicated instrumentation, and it can lead to inadequate sweat samples being collected in newborn babies and young children due to variable sweat production with pilocarpine iontophoresis. We tested the feasibility of using microneedle (MN) patches as an alternative to iontophoresis to administer pilocarpine to induce sweating. Pilocarpine-loaded MN patches were developed. Both MN patches and iontophoresis were applied on horses to induce sweating. The sweat was collected to compare the sweat volume and chloride concentration. The patches contained an array of 100 MNs measuring 600 μm long that were made of water-soluble materials encapsulating pilocarpine nitrate. When manually pressed to the skin, the MN patches delivered >0.5 mg/cm2 pilocarpine, which was double that administered by iontophoresis. When administered to horses, MN patches generated the same volume of sweat when normalized to drug dose and more sweat when normalized to skin area compared to iontophoresis using a commercial device. Moreover, both MN patches and iontophoresis generated sweat with comparable chloride concentration. These results suggest that administration of pilocarpine by MN patches may provide a simpler and more-accessible alternative to iontophoresis for performing a sweat test for the diagnosis of CF.

Evaluation of 2-Hour Post-Dose Efficacy of Lasmiditan for the Acute Treatment of Difficult-to-Treat Migraine Attacks

OBJECTIVE

To identify factors predicting response (2-hour headache pain freedom or most bothersome symptom freedom) to lasmiditan based on individual patient characteristics, migraine disease characteristics, and migraine attack characteristics. Further, efficacy specifically in difficult-to-treat patient/migraine disease characteristics or attack characteristics (ie, historically considered less responsive to certain acute therapies) subgroups was analyzed.

BACKGROUND

Knowledge of factors associated with a positive or negative response to acute treatment would be useful to practitioners prescribing acute treatments for migraine. Additionally, practitioners and patients would benefit from understanding the efficacy of lasmiditan specifically in subgroups of patients with migraine disease characteristics and migraine attack characteristics historically associated with decreased pain threshold, reduced efficacy of acute treatment, or increased burden of migraine.

METHODS

Pooled analyses were completed from 2 Phase 3 double-blind clinical trials, SPARTAN and SAMURAI. Data from baseline to 2 hours after taking lasmiditan (50, 100, or 200 mg) or placebo were analyzed to assess efficacy based on patient characteristics, migraine disease characteristics, and migraine attack characteristics. A total of 3981 patients comprising the intent-to-treat population were treated with placebo (N = 1130), lasmiditan 50 mg (N = 598), lasmiditan 100 mg (N = 1133), or lasmiditan 200 mg (N = 1120). Data were analyzed for the following efficacy measures at 2 hours: headache pain freedom and most bothersome symptom freedom.

RESULTS

None of the analyzed subgroups based on individual patient characteristics, migraine disease characteristics, or migraine attack characteristics predicted headache pain freedom or most bothersome symptom freedom response at 2 hours following lasmiditan treatment (interaction P ≥ .1). For the difficult-to-treat patient/migraine disease characteristics subgroups (defined as those with ≥24 headache days in the past 3 months, duration of migraine history ≥20 years, severe disability [Migraine Disability Assessment score ≥21], obesity [≥30 kg/m2 ], and history of psychiatric disorder), single doses of lasmiditan (100 or 200 mg) were significantly more effective than placebo (P ≤ .002) in achieving both endpoints. Headache pain freedom response rates for higher doses of lasmiditan were numerically greater than for lower doses of lasmiditan. For the difficult-to-treat migraine attack subgroups, patients with severe headache, co-existent nausea at the time of treatment, or who delayed treatment for ≥2 hours from the time of headache onset, both endpoint response rates after lasmiditan 100 or 200 mg were significantly greater than after placebo. Among those who delayed treatment for ≥4 hours from the time of headache onset, headache pain freedom response rates for the 200 mg dose of lasmiditan met statistical significance vs placebo (32.4% vs 15.9%; odds ratio = 2.7 [1.17, 6.07]; P = .018). While the predictors of response interaction test showed similar efficacy of lasmiditan vs placebo across subgroups defined by baseline functional disability (mild, moderate, or needs complete bed rest) at the time of treatment, analyses of lasmiditan efficacy within the subgroup "needs complete bed rest" appeared to show less efficacy (eg, in the 200 mg vs placebo group, 25.9% vs 18.5%; odds ratio = 1.56 [0.96, 2.53]; P = .070).

CONCLUSIONS

Efficacy of lasmiditan 200 and 100 mg for headache pain freedom and most bothersome symptom freedom at 2 hours post-treatment was generally not influenced by the individual patient characteristics, migraine disease history, or migraine attack characteristics that were analyzed. In the analyses of difficult-to-treat subgroups, patients receiving lasmiditan achieved greater responses (2-hour headache pain freedom and most bothersome symptom freedom) vs placebo recipients.

Development of a novel zolmitriptan intracutaneous microneedle system (Qtrypta™) for the acute treatment of migraine

M207 is an investigational intracutaneous microneedle therapeutic system for nonoral zolmitriptan delivery. In a Phase I trial, M207 provided faster absorption with a higher 2 h exposure than oral zolmitriptan. In the pivotal trial evaluating efficacy, tolerability and safety in moderate-to-severe migraine attacks, M207 3.8 mg was superior to placebo in providing freedom from headache pain (42 vs 14%) and freedom from most bothersome symptom (68 vs 43%) 2 h post-dose. Treatment-emergent adverse events were mild and transient and most commonly concerned the application site. In post hoc analyses: pain freedom was sustained in approximately 1/3 of patients; efficacy was observed in migraine headaches that are typically more difficult to treat.