Cutting-edge multifocal contact lens designs have significantly bolstered the optometric toolkit when it comes to myopia control treatments. MYLES HUME examines what is – and what will be – at the disposal of optometrists this year and beyond.
Recent advances in the design and technology behind multifocal soft contact lens (MFSCL) have spurred the development of an entirely new family of treatments specifically for myopia control.
While rigid contact lenses may have maintained a decades-old association with the condition in the form of orthokeratology (OrthoK), the arrival of myopia-specific MFSCLs to the treatment market has significantly strengthened the therapy portfolio, ensuring Australian optometrists are well-equipped for an impending myopia epidemic.
Until last year, CooperVision’s MiSight 1 Day – a dual-focus lens widely available in Australia since 2016 and other markets since 2009 – had been the only soft MFSCL explicitly approved and marketed for myopia control in Australia.
However, CooperVision’s domination of the segment has been challenged by the recent emergence of the NaturalVue Multifocal 1 Day lens, developed by US company Visioneering Technologies (VTI). It was launched in Australia in late 2018, making the country one of the first markets outside of the US to gain access to the product.
Moreover, further competition is appearing on the horizon with Spanish contact lens manufacturer mark’ennovy – in partnership with the Sydney-based Brien Holden Vision Institute (BHVI) – indicating it will enter the arena this year with its MYLO silicone hydrogel contact lens.
MYLO obtained European regulatory approval in February, and the company now expects the product to be expedited through the Australian Therapeutic Goods Administration (TGA) approval process by June, seeing it become the third treatment of its kind available in Australia.
The sector will also be interested to review what emerges from a US$26 million (AU$36.9 m) partnership between Johnson & Johnson Vision, the Singapore National Eye Center and the Singapore Eye Research Institute. Announced last November, the initiative will have a focus on myopia treatments.
Globally, Myopia is predicted to impact 2.6 billion people by the end of 2020. Assuming 30% of those will be 35 years or younger, and 30% of those are interested in contact lens wear, there will be a potential market of 234 million people to treat – and that figure will continue to rise. In Australia alone, the condition currently affects some 4 million people, however, studies suggest this could increase four-fold by 2050 if nothing is done to counter the problem.
Given the statistics, myopia is one of the largest public health issues facing a generation and beyond. However, the latest innovations in MFSCL technology present new opportunities for optometrists and patients, who will ultimately benefit from the technological race to develop cutting-edge treatments.
Expanding optometric toolkit
The arrival of the myopia-specific MFSCLs has coincided with what industry leaders describe as a paradigm shift in the way myopia is perceived. A greater body of clinical information is motivating optometrists to view myopia increasingly as a condition requiring ongoing treatment, as opposed to a mere refractive problem that needs remedying.
According to recent manufacturers’ data, soft MFSCLs for myopia control have been shown to slow refractive error progression by as much as 90%, and axial elongation by 52-55%. Other advantages include; increased self-esteem among paediatric patients, ease of fitting, enhanced hygiene safety and minimal side effects. Evidence suggests children as young as eight can wear them.
As a result – in the four therapy options available; including OrthoK, atropine and spectacles – soft MFSCLs are gathering support as one of the most effective myopia treatments, alongside orthokeratology (OrthoK) – which some consider still to be the gold standard treatment – and, to a lesser extent, atropine.
Although variations of MFSCLs have been prescribed for myopia control in the past, that has been in an ‘off-label’ context without robust clinical data. Importantly, the latest MFSCLs – granted approval for myopia control indications – typically consist of a centre distance design to effectively correct the refractive error, while the lens’ plus power zone(s) work to produce peripheral myopic defocus, one of the factors believed to slow myopia progression and elongation of the eye’s axial length.
Dr Pauline Kang, a lecturer at the University of New South Wales School of Optometry and Vision Science who has studied myopia treatments for more than a decade, said the latest innovations have culminated in a fascinating period for optometrists.
Based on the latest clinical data, she believed MFSCLs appeared to be as effective as OrthoK, which consistently demonstrates an approximate 45% myopia control effect.
Kang said a key advantage for MFSCLs was their ease of fitting compared with OrthoK, which demands specialised clinical training and instrumentation. Due to their ‘one-size-fits-all’ design, and a general requirement for the optometrist to only prescribe the distance power, soft MFSCLs could become accessible to a wider group of eyecare professionals.
Combined with the improved hygiene and comfort associated with daily disposable soft contact lenses, as well as strengthening clinical data, she predicts MFSCLs will become a popular choice.
“I’m sure there will be a big uptake in prescribing of these lenses, providing they have evidence to demonstrate a myopia-controlling effect. I also think more companies will start to bring out their own individual designs,” she said.
“We are seeing some promising results, but it’s important for optometrists to understand who is funding the studies, and they need to be peer-reviewed so that we can be sure of just how robust the studies investigating these lens designs are.”
Visioneering technologies, NaturalVue
Founded in the US in 2008, VTI is the newest player to Australian myopia market with NaturalVue Multifocal 1 Day, a one-day soft lens that was an accidental success as far as myopia control is concerned.
Despite officially launching in Australia in late 2018, VTI’s association with the country dates back to March 2017, when it listed on the Australian Stock Exchange (ASX), raising more than $33 million for its initial public offering at an $88 million market capitalisation.
Since its ASX listing, VTI’s stock price has been on a steady decline from a high of $0.55 in December 2017 to around $0.09 at time of writing, but the company hopes investors will soon take note of its rising net revenue, which tripled to $3.3 million last year.
With plans to enter the lucrative Asian markets, 40% gross profit and a projected FY2019 net revenue of $7 million, this year could result in the company’s biggest yet.
In treating myopia, VTI places its success squarely on the shoulders of the patented optics in NaturalVue, however, the fact they were never intended for this treatment makes its journey all the more fascinating.
In 2006, when current VTI president and CEO Dr Stephen Snowdy became interested in the early development of NaturalVue as a medical venture capitalist, it was only ever designed to treat presbyopia.
The company retained that view for almost a decade, until optometrists began to test the limits of NaturalVue in a new subset of patients.
“When I became involved with the inventor of NaturalVue Multifocal [Dr Richard Giffin] in 2006, there was no mention of the optics being capable of inhibiting myopia progression in children,” Snowdy, who was later appointed VTI CEO in 2013, said.
“By the time we launched the product in 2015, however, the scientific community began to understand the optical factors contributing to progressive myopia in kids, and there was a great theoretical alignment between NaturalVue Multifocal’s design and the optical factors involved in myopia progression.”
US optometrists began experimenting with the lens in myopic children and discovered what Snowdy described as a “profound” slowing effect. (Under US law, health providers can prescribe medical devices how they wish, provided it has Food and Drug Administration clearance. NaturalVue has a very broad US approval for correcting blurry vision).
Today, in a sample size of 141 children wearing the lens for up to four years, VTI reports NaturalVue has consistently demonstrated a 90% decrease in (1.00 diopter) in myopic progression refractive error, as compared to the rate observed prior to wearing the lenses. Additionally, in a subset of 36 children, axial length progression decreased 54.8%, a decrease in progression of 0.23mm at the 12-17 month point.
“The decrease in worsening of vision is something that has not been demonstrated, or even close to demonstrated, with a multifocal contact lens like this,” Snowdy claimed.
He said NaturalVue differed from traditional multifocal contact lenses, which consist of zones, step changes or hard optical edges. The lens is designed with a centre distance power Rx (up to –12.25D), however, the refractive power then rapidly increases until reaching the outer edge of the lens optical zone. The transition is smooth and continuous.
“Its success in creating depth of focus for the presbyopic patient and in slowing of myopia progression in children is very specific to the shape of the rise in power,” he said.
“The key is just how much plus power we get in the lens. We go up 9.0 diopters of tangential power, 3.5D of axial power, in the periphery, relative to the centre of the lens.
“That is something that – until we did it – no one really thought would result in clear vision. No one thought we could make optics like this that are usable in a human vision system because there’s just so much plus power.”
According to Snowdy, the optics result in clear vision at all distances, and negate haloing and ghosting effects. While also slowing myopia progression significantly, he said the visual comfort ensures high compliance rates, a vital factor in effective myopia management.
For VTI, obtaining TGA approval in March 2018 – and the subsequent Australian launch – was considered a major milestone that will pave the way for broader expansion into the Asia-Pacific region.
This year Snowdy expects further penetration into the European markets, where it also has regulatory approval. However, most notably, the company will make a play for lucrative Asian markets such as Hong Kong and Singapore, which have some of the world’s highest myopia rates.
Snowdy said the stringent Chinese market – worth an estimated US$11 billion (AU$15.6 b) – and Japan, rain a long-term goals that require patience and regional partnerships.As it barks on a rapid expansion venture, 2019 could result in a watershed year for VTI and NautralVue as it goes head-to-head with CooperVision’s MiSight – the pioneering contact lens for the segment.
In the development of MiSight 1 Day – the world’s first daily disposable contact lens for myopia management – CooperVision has played a central role in triggering the latest evolution in myopia treatments.
First made available in Hong Kong in 2009, the company’s product is now being distributed with a ‘myopia control indication’ in eight European countries, the Nordic region, Israel, Canada, Singapore, Malaysia and Australasia.
MiSight was first made available to a small number of Australian practitioners in 2011, which helped the company monitor its use in retail optometric practices. Later, in 2012, the company undertook a major international study to build a comprehensive set of clinical data that continues to support its product today.
On the back of promising results and feedback from optometrists, from 2016 CooperVision steadily expanded its distribution. Today, MiSight is prescribed throughout Australia and New Zealand by what the company describes as a large and increasing number of MiSight-accredited optometrists.
The dual-focus design of MiSight involves two correction zones and two concentric treatment zones to create 2.00D of myopic defocus. This apparently causes a consistent treatment effect regardless of gaze direction and pupil size.
Although the optics were vital to MiSight’s success, CooperVision, and optometrists alike, claim a key advantage for the product is its proven capability in a controlled study that is demonstrating a sustained, year-on-year slowing of myopia progression.
The latest three-year results from the ongoing study, released in 2017, show MiSight slowed myopic progression in children by 59%, as measured by mean cycloplegic spherical equivalent (SE), and 52%, as measured by mean axial elongation, when compared to the children in a control group wearing a single vision one-day contact lens. At that point, the control group was also refitted with MiSight and one year later the group exhibited a significantly slower rate of progression that matched that of the test group.
CooperVision ANZ professional services manager Mr Joe Tanner said: “A three-year randomised controlled trial with suitable statistical power is an essential part of what you need to establish efficacy. I have seen a number of claims based on studies without randomisation, without control groups and of much shorter duration.
“To be successful, a treatment must have a sustained effect over a number of years and so we have to conduct the studies to demonstrate this before we can make confident recommendations to patients and parents. Myopia management must be practised in an evidence-based manner and MiSight 1 Day has strong multi-year data to which we will continue to add.”
Looking head, Tanner said CooperVision’s research would also examine how its patients reacted once they reached maturity and no longer required treatment lenses.
“It’s a large and exciting challenge for the profession. There are already hundreds of thousands of myopic children in Australia and over the years many more are likely to join them. We know enough to be confident we can, in many cases, reduce the risks of the adverse consequences of axial elongation,” he said.
mark’ennovy & BHVI, MYLO
With a product that has origins in a 2010 study, Spanish contact lens manufacturer mark’ennovy – in partnership with BHVI – is set to be the third company to release a myopia control soft contact lens in Australia this year.
The company’s MYLO contact lens was granted a CE Mark in late February this year, allowing it to be marketed and sold for myopia management within the European Economic Area.
According to mark’ennovy Asia Pacific managing director Mr Chris Harous, the European clearance will help expedite MYLO through the TGA approval process, with plans to launch in Australia by June, if not sooner.
“The addition of MYLO specifically designed for myopia management is a genuine opportunity for Australian optometrists to now provide another premium treatment option in what is a high growth area for the future of optometry,” Harous said.
“Myopia managent offers something of a game-changer for contact lens practitioners as this process of contact lens fitting, prescribing, dispensing and aftercare has the ability of taking contact lenses from just another retail commodity product back to a prescribed medical device that starts and stays with the eyecare professional, from the first consultation to ongoing treatment of their patient.”
MYLO was born out of a September 2017 exclusive licensing agreement between mark’ennovy and the BHVI. The deal was designed to combine BHVI’s advanced optical designs and mark’ennovy’s manufacturing capabilities to form a portfolio of new soft contact lenses specifically for myopia control and presbyopia.
Ms Yvette Waddell, BHVI’s CEO, said that the design had been shown to slow myopia progression by 31% in children after one year. The two-year efficacy results are being discussed and are due to be published.The monthly replacmeent lens will be available in mark’ennovy’s expansive range of diameters and base curves, personalised for each patient – a key point of difference compared to its competitors, the company claims.
The extended-depth-of-focus (EDOF) technology in MYLO was the brainchild of BHVI’s current head of research and development Dr Ravi Bakaraju, who began exploring improved multifocal lens capability as part of his PhD in 2010.
Over the ensuing years, tireless work was put into refining the BHVI-patented EDOF technology, which was later proven effective in myopes.According to mark’ennovy, MYLO’s EDOF optics result in good vision at all distances, while the design simultaneously renders the global retinal image quality poor behind the retina. This degradation of the image quality behind the retina deters axial elongation.
Waddell said MYLO had no discrete zones of addition powers, helping promote a more comfortable visual experience.“We believe these lenses are bridging the gap in providing a vision performance that is closer to that experienced with single-vision lenses, while also being effective in managing myopia. We believe that one of the barriers to improved uptake and maintenance of contact lens wear for myopia management are the drawbacks in vision performance,” she said.
“We believe the MYLO lens will offer superior myopia management to patients across the world. In particular, we believe the custom-made contact lens segment will continue to grow and the smaller, specialty lens manufacturers will thrive.”
How are they performing?
Paediatric myopia management forms a major part of optometrist Dr Philip Cheng’s practice at Eyecare Concepts in Melbourne, which offers all contact lens options, as well as atropine and spectacle lens treatments.
Although OrthoK remains the preferred treatment in his clinic, Cheng is accredited to prescribe MiSight and recently added the NaturalVue to his therapy options, giving him unique insight into how the products perform.
He said MiSight had shown good results in slowing myopic progression in many patients, and he was also encouraged by CooperVision’s four-year clinical data.
However, in general, he found insertion and removal of soft lenses could be a challenge for younger patients, particularly for some children of Asian heritage who have tighter eyelids. He said parental involvement was an important part of fitting young children successfully with contact lenses for the first time.
Another issue associated with current MFSCLs was the ‘one-size-fits-all’ approach, which meant the lens can occasionally fit too loose or too tight, or be positioned slightly off-centre, leaving some patients to view through the relative plus power portion of the lens, thereby compromising distance vision.
“With MiSight, the first ‘near add’ zone of the concentric design is very close to the centre of the lens, which is great for myopia control. When it works well, the vision is good, but like any other contact lens, it won’t fit every eye. I assess the lenses carefully on the patients’ eyes to ensure they are fitting optimally,” Cheng said.
Incorporating NaturalVue into his practice at the end of 2018, Cheng won’t know for several months how effective it has in controlling myopia in patients he has fitted with the lens.
However, with a high relative plus power and “unique design”, he expects the lens to have good effectiveness in reducing peripheral hyperopic defocus.
Thus far, he has identified several advantages in fitting the NaturalVue lens and the vision quality it provides. Additionally, NaturalVue’s power range (up to –12.25D) makes it accessible to a wider range of patients compared to MiSight (up to –6.00D).
“NaturalVue seems to fit quite well for my paediatric patients and is also quite forgiving with small amounts of lens decentration. It provides clear distance vision even for children with mild astigmatism. The lens shape and optical design is rather different but it works well,” he said.
In the wider context of myopia treatment, Cheng believes OrthoK rains the best therapy option, pointing to the freedom, convenience and comfort of not wearing lenses during the day, and parents feeling in control with the lenses being worn at home.
“OrthoK is more customisable to the patient’s prescription and eye shape, and when fitted properly can correct a wide range of refractive errors including moderate levels of myopia and astigmatism. However, I can see an advantage of multifocal soft lenses over OrthoK for lower levels of myopia (under -1.50D) as well as cases of very high myopia that can be a challenge to fit with OrthoK,” he said.
“There’s also the safety factor – while modern OrthoK treatment has a good safety profile, the wearing of a daily disposable lens has lower risks.”
While the myopia-control MFSCL era may still be in its infancy, strengthening clinical data has seen th become a genuine alternative to more traditional therapies. Eyecare professionals will monitor the near future with interest as more advanced designs test the bounds of myopia treatment, and companies invest in R&D projects to tackle this evolving public health crisis.