Lab Rats series: Activating ‘natural killers’ for cancer with Zumutor

The Bengaluru-founded company’s lead candidate, ZM008, is in phase 1 clinical trials in the US. It is designed to help the immune system’s natural killer (NK) cells recognize and attack cancer cells more effectively, targeting a pathway being explored for its potential against solid tumours. NK cell therapeutics are a promising new frontier in cancer care, and have been attracting billion-dollar deals globally.

“It was a bold move, but thankfully not foolish,” Iyer said, who founded Zumutor in 2013, when original biologics research was still a nascent area in India.

The company has raised more than $30 million in patient capital. In drug discovery, where development can take years and outcomes are often binary, the pressure to establish a route to returns is mounting. Zumutor is accelerating its clinical programmes while pursuing licensing deals with global biopharmaceutical companies over the next two years.

Unlike T cells, which use highly specific receptors to recognize particular antigens, NK cells integrate signals from a range of activating and inhibitory receptors to determine whether a cell should be killed. Cancer cells can exploit inhibitory pathways to evade immune surveillance and escape NK cell-mediated killing.

ZM008 is not a cell therapy: Zumutor is not engineering NK cells for infusion into patients. Instead, the candidate is a fully human monoclonal antibody designed to release an inhibitory signal, enhancing NK cell activation and anti-tumour activity.

The phase 1 programme has reported early clinical signals, including in renal cell carcinoma, while colorectal and head and neck cancers are among the areas of interest. Non-small cell lung cancer has also been added to the clinical programme.

ZM008 is being tested at three sites in the US. Zumutor plans to conduct trials in India next and expects to begin global phase 2 trials next year in regions including India, Iyer said.

Why Zumutor moved to the US

The decision to pursue original drug discovery came after Iyer had spent years working in India's large molecules space. A former Biocon employee, she spent seven years working across enzymes, insulin and early antibody development programmes before launching InbioPro Solutions, a biosimilars startup, in 2007.

Biosimilars are developed to be highly similar to an existing reference biologic, drawing on the scientific foundation established by the original drug. Novel biologics require a different approach: researchers must identify and validate new molecular targets before advancing candidates through preclinical and clinical testing.

India’s pharmaceutical industry has built a substantial ecosystem for generic drug development and, over recent decades, has expanded its capabilities and infrastructure for biosimilars. Original drug discovery, however, depends on the depth of the scientific knowledge base available to researchers, said Manish Diwan, head of the Birac-RDI fund, which falls under the Centre’s ₹1 trillion Research, Development and Innovation (RDI) Initiative and is managed by the Biotechnology Industry Research Assistance Council (Birac).

Zumutor responded by shifting its corporate base to the US in 2016, incorporating there while retaining its Bengaluru company as a wholly owned subsidiary. Iyer credited the move with accelerating the company’s R&D.

Over 10 months, “we shopped extensively. We took advice from the best over there. We asked the right questions of what is the pipeline a company like us should build? How much money would it take? How long would it take? What’s the patent landscape? Would Big Pharma swallow us? Would the competition be too high?” Iyer said.

Zumutor secured $6 million seed funding from Accel Partners, alongside Aarin Capital, IDG Ventures and KITVEN. Most recently, it raised $7.3 million in June in a pre-Series B round led by Accel and Bharat Innovation Fund.

The commercial strategy now rests on moving ZM008 through clinical development while finding partners willing to license the drug in specific territories. Zumutor is in discussions with multiple global biopharmaceutical companies and expects region-specific licensing opportunities to emerge around 2027-28, Iyer said.

Jessica Jani

Jessica has been tracking the pharmaceutical, life sciences and healthcare sector for Mint since November 2024. Based in the country's financial capital, she reports on everything to do with health and medicines. This includes corporate action, patent wars, deals, startup activity and consumer trends. She also keeps a keen eye on the ever-evolving world wellness and preventive health, which moves faster than regulation can keep up. She has a deep interest in what the future of health looks like and how science, innovation, policy and company decisions inform and impact the health of citizens. She has been a reporter for five years, working with publications like The Core and News18 prior to this, covering various sectors like automobiles, real estate, energy, sustainability and urban mobility. Jessica has a bachelor’s degree in English from St Xavier’s College, Mumbai and a postgraduate diploma in media from Sophia’s College, Mumbai. Her work is driven by a desire to decode how macro decisions and events alter and shape the lives of ordinary people. Drop her a mail or a message to discuss business scoops, exciting new medicines and inventions, or your latest wellness routine.