Dostarlimab drug trials: The science behind cancer and the therapy’s future

Cancer treatment has been a critical point for clinical diagnostics. Over the years, various treatment approaches- from naked nucleic acid-based therapy, targeting microRNAs, oncolytic virotherapy, and suicide-gene-based therapy to CRISPR/Cas-9-based therapy. More recently, drug-based therapy has also emerged as a promising area for cancer therapeutics. Regarding drug administration, a major buzz has been created around dostarlimab, whose trials have yielded substantial results. Before this discovery, a series of gene therapeutics were initiated, with varying degrees of success.

Dostarlimab was first developed by AnaptysBio and later licensed to GSK (NYSE:GSK). The trade name for dostarlimab is Jemperli.

FDA approved dostarlimab for women with recurrent or advanced dMMR endometrial cancer in April 2021. In August of the same year, GSK won FDA accelerated approval for dostarlimab for adults with mismatch repair-deficient (dMMR) recurrent or advanced solid tumors.

With advances in medical science, the day is not far when effective cancer-curing drugs will become mainstream. According to Future Market Insights, novel drug delivery systems in cancer therapy are expected to see heightened expansion, forecasting a CAGR of 19.6% during the 2022–2032 assessment period. Furthermore, the industry is likely to reach nearly US$15 billion by the end of 2022. Dostarlimab drug trials comprise a significant proportion of the said growth forecast.

The discovery of dostarlimab comes against a background of an ever-intensifying quest to discover novel drugs for treatment. Despite being wrapped in the stranglehold of a global pandemic, 2021 was a breakthrough year for cancer therapeutics. In a record-setting year, more novel cancer medicines became available at any time in history. This adoption of breakthrough therapies will improve outcomes for millions of cancer patients globally. The focus of this article will be on how dostarlimab is poised to emerge as a highly effective solution to cancer treatment while also considering potential challenges to its adoption in oncology.

Dostarlimab: A first of its kind drug candidate for eliminating cancer

In an astonishing result for an ongoing medical clinical trial, 12 rectal cancer patients were completely cured of the disease post-administration of a drug for six months. Following the administration, these patients were subjected to a series of medical examinations — physical scrutiny, endoscopy, bioscopy, PET scans and MRI scans — with each report detecting no signs of tumors. The initial purpose of this study was to determine whether candidate TSR-042 or dostarlimab, followed by standard chemoradiotherapy, was effective or not.

GSK, the Simon and Eve Colin Foundation, Stand Up to Cancer, Swim across America and the National Cancer Institute of the NIH supported the study.

The study participants with mismatch repair-deficient stage II or III rectal adenocarcinoma received the drug every three weeks for six months. Investigators proposed that the treatment would precede standard chemotherapy and surgery. Patients who had a complete clinical response would not receive either. After at least six months of follow-up, all 12 patients had a complete clinical response with no signs of the tumor.

When this study was published, no patients had received any chemoradiotherapy or undergone surgery, while no cases of progression or recurrence have been reported during follow-ups which ranged from 6 to 25 months. Dostarlimab’s mode of action is to unlock the body’s natural immune system to fight cancer. When administered during immunotherapy, the drug ramps up the immune system to detect cancer and eradicate it. Furthermore, the drug has documented limited severe side effects. To put it in perspective, only 3–5% of patients who consumed dostarlimab exhibited severe complications.

Scientists advise cautious optimism

The Organ Preservation in Rectal Adenocarcinoma (OPRA) trial shows that 88% of tumor regrowth can happen up to 2 years after completion of total neoadjuvant therapy (TNT). According to oncologist Dr. Aju Mathew of the Ernakulam Cancer Center in Kerala, drugs based on the fundamentals of PD-1 inhibitors, like dostarlimab, can be used only in patients with the genetic property of mismatch repair (MMR) deficiency.

As time passes and dostarlimab gains popularity, scientists and doctors worldwide are cautiously optimistic regarding the drug’s efficacy in treating various kinds of cancer at multiple stages. Dr. Hanna K. Sanoff, an oncologist with the University of North Carolina at Chapel Hill, says, “a clinical complete response to the treatment is not a surrogate for long-term cancer control.” Hill acknowledged that checkpoint inhibitors such as dostarlimab can have long-term effects. However, he added that “cancer regrowth is generally expected to still occur in a minority of patients where tumors are managed nonoperatively, let alone with an experimental treatment like this.”

It is still unknown whether the resulting clinical response to dostarlimab equates to a cure, as large-scale positive results are needed to be sure of the drug’s benefits. In addition, the study was conducted only on rectal cancer patients. So the question that arises in the minds of the doctors is how impressively the drug will work in treating other cancers.

Bearing these doubts in mind, the adoption of dostarlimab in oncology is projected to face some significant roadblocks. Researchers are increasingly investigating how a drug can completely cure cancer without going through long, painful treatments comprising surgery or chemotherapy. Furthermore, there is still a lot unknown about cancer drugs, so further research is required to inform the development of new cancer therapies.

Looking forward

Cancer is one of the leading causes of death globally. Its treatment impacts not only the life of the patients but also those around them. With advancements in medical science, scientists are working towards finding impressive therapies for cancer.

The study on dostarlimab, published in the New England Journal of Medicine, has given great hope to the global healthcare sector that rectal cancer can be completely cured. Furthermore, the success of dostarlimab in treating different cancers or Phase 3 trials remains a question. Even though dostarlimab has taken over the headlines, many more drugs are awaiting clinical approvals.

Looking forward, if the drug is proven highly efficient in future studies, the cost is one important factor to consider. In the U.S., the price tag is about $11,000 per dose. The cost of the drug needs to come down to make it affordable to a major population suffering from cancer because 70% of all cancers are expected to occur in low- and middle-income countries.

All said and done, dostarlimab treatment is paramount in studies considering the alarming rise in the number of rectal cancer patients. However, the biggest relief is that, as per research, there were no significant side effects from the drug, leading to improvement in the general condition of the cancer-stricken life.

Sudip Saha, the ‘Mozart of market research, a moniker given to him by his peers, is the COO of ESOMAR-certified Future Market Insights. Saha is a member of the Greater New York Chamber of Commerce. Saha guides the strategic and tactical leadership of COO functions and is involved in the strategy, execution, financial position and market performance of FMI. You can connect with Sudip on LinkedIn and Twitter.