Year-to-date gain: 284.06 percent; market cap: AU$193.79 million; share price: AU$1.325

First up on this list of best-performing ASX small cap biotech stocks is clinical-stage LTR Pharma, which is working to commercialise a new PDE5 inhibitor intranasal spray technology designed to treat erectile dysfunction in 10 minutes or less. Known as SPONTAN, the intranasal spray has successfully completed a Phase I human proof of concept study in which its delivery technology was shown to reach maximum concentration five times faster than oral PDE5 inhibitors.

Shares in LTR Pharma started the year off at AU$0.33. The stock’s value reached AU$0.93 on June 11, shortly after the results of the Phase 1 SPONTAN were released on June 7.

LTR Pharma's share price spiked again in mid-August to a year-to-date high of AU$1.38 following a spate of positive newsflow. On August 5, the company announced that SPONTAN had been prescribed to first patients under Australia’s Therapeutic Goods Administration (TGA) Special Access Scheme. A few days later came the news that a second men’s health clinic had begun prescribing SPONTAN under the scheme.

The biggest hike came after the August 13 announcement that LTR signed a co-development agreement with Aptar Pharma, a subsidiary of Aptar Group (NYSE:ATR), to commercialise SPONTAN in the US and other global markets. Another major milestone came on August 16 with first patients prescribed under the TGA Authorised Prescriber scheme, allowing for “broader patient access for patients with a particular medical condition rather than on a case-by-case basis,” stated the press release.

Year-to-date gain: 80.72 percent; market cap: AU$35.65 million; share price: AU$0.135

The biotech company Amplia is advancing a pipeline of focal adhesion kinase inhibitors for cancer and fibrosis. Amplia’s lead candidate is narmafotinib (AMP945), which is currently in Phase 1b/2a studies targeting pancreatic cancer, and in the planning stages for a Phase 2 study targeting ovarian cancer.

Shares in Amplia Pharma have spent most of the year in a trading range of AU$0.06 to AU$0.08. On July 25, the company released positive news pertaining to sustained reduction in tumour size in three out of 26 patients during its Phase 2a clinical trial for Narmafotinib in combination with standard-of-care chemotherapy in advanced pancreatic cancer patients. In response, shares spiked from AU$0.06 to AU$0.10 the same day.

A few weeks later, an additional patient in this clinical study presented with similar results, bumping Amplia’s stock value up to AU$0.14 on August 6. If the trials can achieve a reduction in tumour size in a total of 6 patients, an additional 24 patients may be enrolled in the study.

Since then, Amplia’s shares have managed to sustain that price level on a series of further positive developments. On August 7, the company was granted a key patent for narmafotinibin Japan and Europe, extending patent protection in these markets until at least 2040. The following week, the company received an R&D tax incentive refund of AU$3.18 million for the 2023/2024 financial year.

Most recently, on August 21, a fifth patient recorded a reduction in tumour size during the Phase 2a clinical trial. “The continued positive data from the trial is extremely gratifying and at this rate we remain confident we will reopen recruitment in early October,” Amplia CEO Dr. Chris Burns stated.

Year-to-date gain: 62 percent; market cap: AU$104.89 million; share price: AU$0.81

Argenica Therapeutics is developing novel neuroprotective therapeutics. The company’s lead product candidate is ARG-007, a neuroprotective peptide candidate intended to protect brain cells and reduce cell death during a stroke and other types of neural injuries.

Shares in Argenica have experienced a degree of volatility for the first half of the year, trading in a range of AU$0.47 to AU$0.67 before jumping to AU$0.88 on June 19 and on to a year-to-date high of AU$0.93 on July 8.

On March 25, the company reported that the US Food and Drug Administration had granted ARG-007 a rare pediatric disease designation for the treatment of hypoxic ischaemic encephalopathy in newborn term infants.

Much of the top news coming out for Argenica this year has related to its Phase 2 clinical trial for its neuroprotective drug ARG-007 in acute ischaemic stroke patients, for which the first patient was successfully dosed in late March.

The following month, the company reported that after reviewing the safety data of the first five patients dosed in the trial, the Data Safety Monitoring Board (DSMB) recommended the study continue without requiring modifications to the study. Soon after, shares in Argenica began their steady climb. In mid-May, Argenica shared that a pre-clinical ferret animal trial of ARG-007 in treating traumatic brain injuries showed a significant reduction in damage to brain cells.

On July 23, the company reported that eight of the ten hospitals participating in the Phase 2 clinical trial had been activated with the remainder set to start up by the end of the month. At that time, a total of 20 patients had been enrolled out of a planned 92 by the close of the enrollment period at the end of 2025.

Argenica’s shares have managed to stay above the AU$0.80 level for much of the third quarter to date.

Year-to-date gain: 61.54 percent; market cap: AU$36.11 million; share price: AU$0.21

Biotech penny stock Cynata Therapeutics is a clinical-stage stem cell and regenerative medicine company developing cell therapies based on its proprietary therapeutic stem cell platform technology, Cymerus. Its clinical pipeline includes a variety of indications such as graft-versus-host disease (GvHD), osteoarthritis, diabetic wounds and acute respiratory distress syndrome.

Cynata shares kicked off the year at a value of AU$0.12, and had their first big jump on Feb 26 to AU$0.23 per share. This came the same day as the company announced encouraging initial data from its Phase 1 clinical trial of CYP-006TK in diabetic foot ulcers showing a greater percentage of reduction in wound surface area in the active CYP-006TK group compared to the control group.

The following month, Cynata received regulatory and ethics approval in the European Union for its Phase 2 clinical trial of CYP-001 in high-risk acute GvHD. On May 22, the company announced the publication of two-year follow-up data from its CYP-001 in patients with steroid-resistant acute GvHD in the peer-reviewed journal Nature Medicine.

“Two-year overall survival rate in patients with steroid-resistant acute GvHD was 60 (percent),” stated the press release. Shares in Cynata went on to hit its year-to-date peak of AU$0.34 on May 31.

Year-to-date gain: 8.48 percent; market cap: AU$442.1 million; share price: AU$0.36

The last ASX small cap biotech company on this list is Immutep, which is focused on developing autoimmune and cancer immunotherapy treatments. Its drug pipeline is built around eftilagimod alpha, its proprietary lymphocyte activation gene-3 (LAG-3) protein, an immune checkpoint molecule involved in the regulation of the immune system. LAG-3 was discovered by Immutep Chief Scientific Officer Frédéric Triebel.

The first patient was enrolled and safely dosed in the company’s INSIGHT-005 Phase I trial in early January. This is a jointly funded study with Merck (NYSE:MRK) to evaluate eftilagimod alpha in combination with Merck's BAVENCIO (avelumab) in up to 30 patients with metastatic urothelial carcinoma.

On March 5, Immutep shared that data from the safety lead-in of its AIPAC-003 trial shows 90 milligrams of eftilagimod alpha in combination with paclitaxel for treatment of HR-positive, HER2-negative, low metastatic breast cancer is safe and well tolerated. The company’s share price reacted with a bump up from AU$0.38 to AU$0.41 on March 8.

Another share price jump came from the April 24 release of positive preliminary topline results from its TACTI-003 Phase 2b trial evaluating eftilagimod alpha in combination with Merck’s anti-PD-1 therapy KEYTRUDA as first-line treatment of recurrent, metastatic head and neck squamous cell carcinoma patients with negative PD-L1 expression. The stock price jumped from AU$0.35 to AU$0.45 that day.

Shares in Immutep reached a year-to-date high on May 7 to close at AU$0.48 a few days after the release of initial clinical data from its EFTISARC-NEO Phase 2 trial evaluating eftilagimod alpha in combination with radiotherapy and KEYTRUDA for patients with soft tissue sarcoma.

However, results from its TACTI-003 Phase 2b trial, while relatively positive, were not as expected and the market reacted. This led the value of its stock to decline from AU$0.44 on June 26 to a low of AU$0.28 on July 3.