madman
Super Moderator
Key clinical findings included:
- Ultra-rapid onset – SPONTAN reached peak plasma concentration (Tmax) in a median of 10 minutes versus 45 minutes for oral tablets, with mean values of 12 minutes versus 56 minutes respectively.
- Superior efficiency – Despite half the dose, SPONTAN achieved higher bioavailability per milligram, with dose-normalised Cmax of 2.58 ng/mL/mg versus 1.67 ng/mL/mg for oral administration.
- Comparable duration – Similar half-life of ~4 hours for both formulations, supporting sustained therapeutic effect.
- Manageable tolerability – Safety profile consistent with the PDE5 inhibitor class, with no serious adverse events reported.
- Publication validates five times faster onset, strengthening regulatory pathway and physician adoption
- LTR Pharma is targeting the US$3.7 billion ED market with SPONTAN and its other intranasal vardenafil formulation ROXUS
Special Report: Results of LTR Pharma’s phase I pharmacokinetic (PK) study of SPONTAN, its nasal spray mist to treat erectile dysfunction, have been published in the peer-reviewed European Journal of Pharmaceutical Sciences.
The publication provides independent validation of SPONTAN – LTR Pharma’s (ASX:LTP) lead intranasal vardenafil formulation for ED – including ultra-rapid onset, showing peak plasma concentrations in just 10 minutes compared with 45 minutes for conventional oral ED tablets.
Mean Tmax values were 12 minutes for SPONTAN versus 56 minutes for tablets, confirming consistent rapid absorption across participants.
Tmax refers to the time it takes for a drug to reach its maximum concentration (Cmax) in the bloodstream after administration.
The European Journal of Pharmaceutical Sciences is a leading international peer-reviewed publication that highlights high-impact research in pharmaceutical sciences and drug delivery.
Publication in the journal requires rigorous peer review by independent scientific experts and represents significant third-party validation of clinical data quality.
LTR Pharma said publication in the journal adds substantial credibility to LTR’s regulatory dossier as the company advances towards full commercialisation.
"This peer-reviewed validation marks a transformative milestone for LTR Pharma. We now have independent scientific confirmation that our technology delivers what ED patients have been seeking for decades - true spontaneity,” executive chairman Lee Rodne said.
About the PK study
The randomised crossover study in 18 healthy male volunteers compared SPONTAN nasal spray (5 mg vardenafil) with oral vardenafil tablets (10 mg).Key clinical findings included:
- Ultra-rapid onset – SPONTAN reached peak plasma concentration (Tmax) in a median of 10 minutes versus 45 minutes for oral tablets, with mean values of 12 minutes versus 56 minutes respectively.
- Superior efficiency – Despite half the dose, SPONTAN achieved higher bioavailability per milligram, with dose-normalised Cmax of 2.58 ng/mL/mg versus 1.67 ng/mL/mg for oral administration.
- Comparable duration – Similar half-life of ~4 hours for both formulations, supporting sustained therapeutic effect.
- Manageable tolerability – Safety profile consistent with the PDE5 inhibitor class, with no serious adverse events reported.
While the study specifically evaluated SPONTAN, the PK data support the company’s broader intranasal delivery platform for vardenafil, which also includes ROXUS.
Both products leverage the same rapid-onset technology, providing LTR with multiple commercial opportunities in different market segments from a single validated drug delivery platform.
Targeting increased spontaneity
Importantly, the publication notes that current oral PDE5 inhibitors face significant limitations, including delayed onset of 30 minutes to two hours, reduced efficacy with food intake, and the need for careful timing around sexual activity.These factors contribute to discontinuation rates of ~4% per month, with lack of spontaneity cited as a primary reason for treatment abandonment.
The study authors concluded that “intranasally delivered vardenafil is associated with more rapid onset of action with similar plasma concentrations”.
They said that “this differential pharmacokinetic profile has potentially important clinical implications given the overall safety and efficacy profile of PDE5 inhibitors in the treatment of ED, especially in men seeking sexual spontaneity”.
Chief medical officer Professor Geoff Strange noted the peer-reviewed publication provided robust scientific validation of SPONTAN’s “game-changing pharmacokinetic profile”.
“The data clearly demonstrate that our intranasal delivery technology achieves the desired therapeutic levels in under 10 minutes – addressing the spontaneity challenge that drives part of the 50% of patients discontinuing oral ED treatments within their first year,” he said.
“From a clinical perspective, this represents a fundamental advancement in how PDE5 inhibitors can be administered, with the potential to significantly improve treatment adherence and patient satisfaction."
SPONTAN is currently available in Australia through the Therapeutic Goods Administration Special Access Scheme, while it is targeting approval in other key markets.
LTR Pharma is advancing a US Food and Drug Administration (FDA) regulatory submission via the 505(b)(2) pathway for SPONTAN approval with the US ED market valued at US$3.7 billion.
The company said the journal publication strengthens its clinical evidence package for regulatory authorities.
