Calla Lily Clinical Care has partnered with Merck to support the intravaginal drug delivery platform Callavid in an effort to improve how vaginal medicines are given.

The collaboration will continue development of Callavid, described as a leak-resistant device that addresses challenges with self-administered vaginal therapies.

Callavid uses a small, tampon-shaped device with an integrated absorbent liner. It is inserted, remains in place during drug absorption, then is removed.

The platform is intended for use with medicines in fertility treatment, oncology and hormone therapy. Administration via the vaginal route can prompt patient anxiety about positioning, dosing accuracy and leakage.

The partnership is the first industry collaboration for the Callavid technology, which was developed by Calla Lily Clinical Care.

Thang Vo-Ta, co-founder and chief executive of Calla Lily Clinical Care, said: “This collaboration with Merck marks an important milestone in the development of Callavid, our novel vaginal drug delivery platform.

“Merck’s scientific heritage and forward-looking approach to innovation make them an ideal partner as we work to address long-standing unmet needs in women’s health.

“By improving how vaginal therapeutics are delivered and experienced, Callavid has the potential to enhance both patient outcomes and quality of life.

“We see this collaboration as a meaningful step towards translating our technology into real-world clinical and patient impact.”

Calla Lily Clinical Care is seeking to develop what it describes as the world’s first drug-device combination product to prevent threatened miscarriage and for IVF luteal phase support, the phase after ovulation when the body produces progesterone to support early pregnancy.

The device is also being developed to deliver therapeutics for oncology, menopause, infectious diseases and live biotherapeutics to reduce repeated antibiotic use.

Dr Lara Zibners, co-founder and chairman of Calla Lily Clinical Care, said: “Our initial engagement with Merck through the Merck Innovation Challenge in October 2024 was an important moment of alignment around the need for more patient-centric innovation in women’s health.

“As both a clinician and a patient, I have seen how profoundly drug delivery can shape treatment experience.

“This collaboration builds on that early dialogue and reflects a shared interest in rigorously exploring new approaches that may improve how therapies are delivered and experienced by patients.”

Transdermal HRT best protects bone density in women with functional hypothalamic amenorrhoea, a condition that stops periods, a review of trials has found.

The meta-analysis pooled randomised clinical trials involving 692 participants and found transdermal hormone replacement therapy and teriparatide increased bone mineral density by between 2 and 13 per cent.

Functional hypothalamic amenorrhoea can follow anorexia or intense exercise. Bone mineral density measures bone strength and the amount of mineral in bone.

Around half of women with the condition have low bone mineral density, compared with about 1 per cent of healthy women, and their fracture risk is up to seven times higher.

The research was conducted by scientists at Imperial College London and Imperial College Healthcare NHS Trust.

Professor Alexander Comninos, senior author of the study and consultant endocrinologist at the trust, said: “Bone density is lost very rapidly in FHA and so addressing bone health early is very important to reduce the lifelong risk of fractures.

“Our study provides much needed comparisons of all the available treatments from all available studies.

“Clearly the best treatment is to restore normal menstrual cycles and therefore oestrogen levels through various psychological, nutritional or exercise interventions – but that is not always possible.

“The foundation for bone health is good calcium and vitamin D intake (through diet and/or supplements) but we have additional treatments that are more effective.”

When FHA is diagnosed, clinicians first try to restore periods through lifestyle measures, including psychological and dietary support, but these can fail. Guidelines then recommend giving oestrogen, though the best form was unclear.

The team reviewed all prior randomised trials comparing therapies, including oral and transdermal oestrogen, and also assessed teriparatide, a prescription bone-building drug used for severe osteoporosis.

They found no significant benefit for oral contraceptive pills or oral hormone therapy.

A recent UK audit reported that about a quarter of women with anorexia-related FHA are prescribed the oral contraceptive pill for bone loss; the study suggests using transdermal therapy instead.

Comninos said: “Our goal is simple: to help women receive the right treatment sooner and to protect their bone health in the long-term.

“We hope this study provides clinicians with better evidence to choose transdermal oestrogen when prescribing oestrogen and so inform future practice guidelines.

“Right now, millions of women with FHA may not be receiving the best treatments for their bone health.”