Avacta Group PLC (AIM: AVCT) shares rise on dual payload breakthrough: Is a clinical re-rating next?

Avacta Group PLC (AIM: AVCT) saw its shares edge up 3.45 percent to 66.00 GBX on October 27, 2025, after the clinical-stage biopharmaceutical company unveiled preclinical data for its first-in-class dual payload peptide drug conjugates at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics in Boston. The share price movement, coupled with a nearly five million-share volume surge and on-book turnover of £16,910.52, reflected renewed interest in the tumor-activated oncology delivery platform that underpins the company’s pre|CISION strategy.

The announcement focused on the preclinical performance of AVA6207, a novel drug conjugate that delivers two therapeutic agents in a single small molecule format. This dual payload delivery model is designed to overcome tumor resistance and maximize therapeutic control while reducing systemic toxicity. The company’s stock has moved within a wide range in the past year, oscillating between a low of 27.25 GBX and a recent high above 70 GBX, underscoring its volatility and the market’s sensitivity to pipeline updates.

Avacta Group PLC is seeking to position its pre|CISION platform as a disruptive approach to combination cancer therapy, one that does not rely on biologic formats like antibody drug conjugates. The stock’s 3.45 percent rise on the day of the announcement may reflect early-stage investor optimism, but analysts continue to view the company as a high-risk, high-reward play that requires strong clinical progression and funding discipline to achieve a valuation re-rating.

What makes Avacta’s dual payload approach a potential step-change in targeted cancer therapy?

Avacta Group PLC has taken a distinctive path in the oncology therapeutics landscape by developing a peptide drug conjugate platform that enables the simultaneous release of two drugs at the tumor site. AVA6207, the company’s lead dual payload candidate, utilizes fibroblast activation protein-mediated cleavage to selectively release a combination of a microtubule inhibitor (monomethyl auristatin E) and a topoisomerase I inhibitor (exatecan).

Unlike traditional antibody drug conjugates, which are large biologics and often limited by poor tumor penetration and complex manufacturing, Avacta Group PLC’s peptide drug conjugates are small molecule constructs. These offer better tissue permeability, lower off-target toxicity, and a simpler manufacturing pathway. The dual payload concept is particularly important in oncology, where combination therapies are increasingly favored for targeting tumors with heterogeneous resistance mechanisms.

The company has also introduced a second configuration that combines exatecan with inhibitors of the DNA damage response pathway, such as ATR and PARP inhibitors. This combination exploits tumor vulnerabilities in DNA repair processes to enhance the cytotoxic effects of exatecan. The resulting synergy offers a strategic advantage in treating highly resistant solid tumors.

According to the company’s presentation, the dual payload design was validated in 2D and 3D tumor spheroid models. These studies showed that both payloads were released simultaneously upon FAP activation and demonstrated significant tumor selectivity. IC50 values for cytotoxicity in FAP-positive environments ranged between 2 and 9 nanomolar, while in FAP-negative contexts the compounds were significantly less active, confirming strong tumor targeting.

How did Avacta’s share price and volume react to the preclinical announcement, and what are investors watching now?

The share price of Avacta Group PLC increased by 3.45 percent to close at 66.00 GBX on October 27, 2025, following the release of the preclinical data. The stock opened at 64.50 GBX and reached an intraday high of 66.00 GBX, closing the session with upward momentum and a bid-offer spread of 68.00 to 70.00 GBX.

Trading volume spiked to nearly five million shares, indicating heightened investor interest. On-book turnover reached £16,910.52. This followed a period of recovery for the stock after it dipped below 30 GBX earlier in 2025. The strong market response suggests that the new scientific milestone has the potential to reposition the company in the eyes of investors who had previously discounted the pipeline’s valuation due to its preclinical status.

Technical analysts are now closely monitoring whether the share price can break above the key 70.00 GBX resistance level. If the current momentum sustains and aligns with additional disclosures—such as regulatory filings or partner announcements—traders may position for a breakout toward the previous peak of 74.00 GBX.

What do institutional investors think about Avacta’s platform and funding outlook?

Despite the share price recovery, Avacta Group PLC continues to operate in a high-risk zone from an institutional perspective. As of its last full-year report, the company generated less than £120,000 in revenue while incurring annual net losses exceeding £40 million. Market capitalization has stabilized around £250 million, implying that investors are pricing in platform potential rather than current financial performance.

Institutional sentiment remains cautious, with many funds waiting for clear signs of clinical progression before increasing exposure. The company’s lead candidate, AVA6000 (FAP-Dox), previously demonstrated a 100-to-1 tumor-to-plasma ratio in early studies and allowed dosing up to four times that of conventional doxorubicin with minimal systemic toxicity. While this helped validate the pre|CISION platform, investors are now looking for similar pharmacodynamic and safety confirmation in dual payload candidates like AVA6207.

Concerns persist around funding, particularly given the company’s high burn rate. A future equity raise remains likely unless non-dilutive partnerships or licensing agreements are secured in the near term. Investors are tracking upcoming disclosures around Investigational New Drug (IND) filings, early-phase trial enrollment, and potential partnering with pharmaceutical companies that could reduce capital intensity.

How does Avacta’s technology compare with dual payload antibody drug conjugates from larger biopharma companies?

Dual payload antibody drug conjugates have recently gained attention from companies such as Seagen, Daiichi Sankyo, and ImmunoGen, with constructs that aim to co-deliver multiple cytotoxic or immunomodulatory agents in a single biologic format. However, these large-molecule designs often face challenges related to tumor penetration, off-target effects, and manufacturing complexity.

Avacta Group PLC’s peptide drug conjugates, by contrast, are small molecules engineered with self-immolative linkers that respond to FAP activity. This enables the simultaneous release of both drugs upon a single cleavage event. The company’s preclinical data demonstrated that the released payloads retained their mechanism of action. Biomarkers associated with each drug—such as tubulin depolymerization for monomethyl auristatin E and DNA damage markers for exatecan—were observed exclusively in FAP-positive tumor cells.

In three-dimensional tumor-fibroblast co-culture models, the dual payload compounds demonstrated a bystander effect, killing both FAP-positive and FAP-negative tumor cells. This finding is particularly relevant in treating heterogeneous tumors where not all cells express the same target. The bystander mechanism increases the therapeutic footprint within the tumor microenvironment, enhancing overall efficacy.

What milestones and risks are investors monitoring as Avacta heads into 2026?

Looking ahead, the most closely watched milestone is whether Avacta Group PLC can file an IND and initiate first-in-human studies for AVA6207 or similar dual payload constructs. The timing of this clinical transition will likely define the trajectory of the company’s valuation in 2026.

Investors are also monitoring for signs of commercial partnerships or licensing agreements that could bring in milestone payments or reduce capital expenditure. Absent these, the company may need to raise additional capital through equity issuance, which would dilute existing shareholders.

Scientific risks include the possibility that dual payload constructs do not maintain their efficacy or safety in human models. Operational risks include manufacturing scalability, intellectual property protection, and regulatory hurdles in different jurisdictions.

If successful, Avacta Group PLC could position itself as a next-generation oncology innovator capable of addressing highly resistant tumors through intelligent, tumor-specific drug design. If execution falters, the company risks being lumped into the broader category of preclinical biotech firms struggling to bridge the gap between promising science and commercial outcomes.

What are the key takeaways from Avacta Group PLC’s dual payload update and stock movement?

• Avacta Group PLC (AIM: AVCT) shares rose 3.45 percent to 66.00 GBX on October 27, 2025, after presenting preclinical data for its dual payload peptide drug conjugates at the AACR-NCI-EORTC conference.
• The dual payload approach enables tumor-activated release of two complementary therapies—exatecan and either MMAE, ATR, or PARP inhibitors—via a single FAP-mediated cleavage event.
• Preclinical models demonstrated tumor-specific cytotoxicity, biomarker-confirmed mechanism activation, and bystander killing in 3D spheroid cultures, supporting the platform’s targeting precision.
• The pre|CISION® platform builds on earlier AVA6000 results and may expand to address up to 90 percent of solid tumors through combination delivery strategies.
• Nearly 5 million shares were traded on the day of the announcement, with strong buy-side interest and bid-offer activity suggesting heightened investor focus.
• Institutional sentiment remains cautious, with investors monitoring for IND filings, clinical initiation of AVA6207, and potential licensing deals in 2026.
• Risks include execution delays, dilution through future capital raises, and the challenge of translating strong preclinical data into human therapeutic outcomes.
• Analysts see Avacta Group PLC as a high-beta, high-reward oncology platform story with potential for re-rating if clinical progress aligns with preclinical promise.