Nuclear Medicine's Next Stop: From "Crossing the River by Feeling Novartis's Stones" to Boldly "Pioneering New Paths"

Ask AI: How can the radiopharmaceutical industry break through homogeneous competition and achieve innovation?

“Science and Technology Innovation Board Daily” March 20th (Reporter: Xu Hong)
Novartis’s latest financial report shows that its flagship radioligand therapy (Radioligand Therapy, RLT) Pluvicto (177Lu-PSMA-617; Chinese brand name: Paiweituo) achieved global sales of $1.994 billion in 2025, a 42% increase year-over-year.

While not the industry’s top performer, this is certainly encouraging.

“Raising the annual sales of a new drug to $2 billion in just three years is undoubtedly a strong boost for the radiopharmaceutical industry,” said an attendee at the BIOCHINA 2026 (11th) Bio Industry Conference.

Domestic radiopharmaceutical R&D has already shown vigorous growth. Yu Chunjing, Director of Nuclear Medicine at Jiangnan University Affiliated Hospital, shared that in December 2025 alone, the hospital’s nuclear medicine department approved over ten ethics reviews for investigator-initiated trials (IIT) of radiopharmaceuticals.

“From these projects, we can clearly see the development trend of domestic radiopharmaceuticals, especially the increasing diversity in isotope applications. Previously, our IIT studies mainly used isotopes like Gallium-68 and Lutetium-177, but among the recently approved projects, new isotopes such as Lead-203, Lead-212, and even multiple Zirconium-89 labeled antibodies are included,” he said.

Currently, Paiweituo has been approved in China for two indications in advanced prostate cancer, making it the first and currently the only targeted radioligand therapy approved for PSMA-positive advanced prostate cancer. In January 2026, Paiweituo was officially commercialized, with initial patients across multiple regions receiving injections.

For a long time, due to its radioactive nature, radiopharmaceuticals—these new anti-cancer weapons capable of “locating and killing tumors with one shot”—have always been shrouded in mystery in the public eye. But now, as Paiweituo enters clinical use, this veil is quietly being lifted.

▌New Radiopharmaceuticals: Unlocking a New Paradigm for Precise Tumor Treatment

When mentioning hospital nuclear medicine departments, most people might feel unfamiliar. Perhaps images of staff in lead aprons working behind lead-shielded fume hoods come to mind… This familiar yet strange scene adds a layer of mystery to radiopharmaceuticals (also called radioactive drugs).

Song Shaoli, Director of Nuclear Medicine at Fudan University Shanghai Cancer Center, explained that although radiopharmaceuticals carry the “nuclear” label and seem different, aside from strict requirements on usage locations and protective measures, their mechanisms of action and expected efficacy are well-established.

Paiweituo is a new type of radiopharmaceutical. Its core mechanism is like installing a carefully crafted “micro-missile” into prostate cancer cells: attaching the therapeutic radionuclide 177Lu to PSMA ligands, forming 177Lu-PSMA-617. After intravenous injection, this micro-missile can accurately recognize cancer cells, delivering 177Lu precisely into the tumor via ligand-receptor binding, directly targeting tumor lesions, efficiently killing tumor cells, and achieving precise tumor clearance while maximally protecting normal tissue.

Of course, radiopharmaceuticals have their own particularities. Many isotopes have short half-lives, which makes production, transportation, and clinical use highly time-sensitive. From manufacturing to injection into patients, the entire process is a race against time.

Song explained with an example: “For Paiweituo, the effective period after calibration is about five days. Currently, Paiweituo is entirely imported. From overseas order to hospital delivery takes about three days, so once it arrives, we need to use it within two days; otherwise, the radioactivity will decay and lose efficacy.”

He also detailed the clinical workflow: “Once the drug arrives at the hospital, we promptly arrange beds, complete admission procedures, and administer the drug within the next day. Paiweituo is given via intravenous injection, which takes about 10-15 minutes. After administration, patients rest in the ward, and we perform whole-body SPECT/CT imaging at 4 hours or 24 hours to observe the distribution of the drug in the body. Usually, patients can be discharged 24 hours later.”

Paiweituo is mainly used to treat metastatic castration-resistant prostate cancer (mCRPC), especially for patients who have exhausted other clinical options. Studies show that over 90% of mCRPC patients have high PSMA expression, making them potential candidates for this therapy.

In practice, patients are first screened with PSMA PET/CT scans; only those with high PSMA expression in metastases are treated with this drug.

“Because tumors in advanced patients are highly heterogeneous, combining imaging modalities for more precise screening of potential beneficiaries is increasingly important. As treatment progresses, clinical practice increasingly recommends combined PSMA and 18F-FDG imaging, which may better identify suitable patients,” said Director Song.

Due to individual differences, the treatment effect of Paiweituo varies. Generally, patients with high PSMA expression and negative FDG scans tend to respond well. “But if the tumor shows low or no PSMA expression, they are not suitable for Paiweituo,” she added.

The “diagnosis and treatment integration” of radiopharmaceuticals is particularly noteworthy. Before therapy, diagnostic PET/CT imaging with diagnostic agents locates and quantifies tumors; after treatment, SPECT/CT imaging observes drug distribution, making the entire process “visualized” and allowing “visible efficacy.”

Song explained that compared to traditional methods, PSMA PET/CT imaging “lights up” tumors and plays a vital role in prostate cancer management, especially in detecting small lesions. Clinically, 3-4mm PSMA-high metastatic lymph nodes are often found, which are easily missed by ultrasound or MRI.

▌The Other Side of the Coin: Homogeneous Competition and Differentiation Breakthroughs

Although radiopharmaceutical development started early, traditional therapies mostly lacked precise targeting. It wasn’t until Novartis’s milestone products—Lutathera (2018) and Pluvicto (2022)—were approved in the US that the industry truly entered a new chapter of targeted precision therapy.

As a leader in the field, Novartis not only validated the technical and commercial feasibility of radiopharmaceuticals but also paved a path for others, making “following Novartis across the river” a practical choice for many companies.

However, there is a flip side. The success of Pluvicto (targeting PSMA) and Lutathera (targeting SSTR) has, while confirming the value of these targets, also led to a wave of follow-up research focusing on imitation and improvement, mainly centered on “beta-emitting isotopes + PSMA/SSTR targets,” resulting in significant pipeline homogeneity.

This phenomenon has attracted widespread industry concern and reflection. Many experts at the conference pointed out: “Choosing mature targets is easier for product development, but after success, how much market opportunity remains?”

Marcel Reichen, Chief Strategy Officer of Ratio Therapeutics, an emerging US radiopharmaceutical company, noted that compared to American firms emphasizing differentiation, Chinese companies, despite rapid development and numerous pipelines, often have highly similar molecular structures. Their thinking and investment in differentiation are still insufficient.

The root cause lies in the complexity of radiopharmaceutical R&D, which far exceeds that of ordinary drugs. To reduce risks, companies tend to adopt conservative strategies. On one hand, ideal targets must meet strict conditions: high expression on tumor cell surfaces and minimal expression in normal tissues—such targets are very limited.

On the other hand, the radioactive nature of these drugs prevents them from having the ample production, quality control, and inventory time that conventional drugs enjoy. Every step must prioritize “timeliness” and “safety,” making manufacturing processes and quality control (CMC) extremely challenging and significantly increasing the difficulty for domestic radiopharmaceuticals to go global independently.

Even for approved therapies, clinical optimization remains possible. Many current doses are based on maximum tolerated doses, but several clinicians suggest that lower doses may still achieve good efficacy in some patients.

“Any radionuclide therapy still faces the challenge of dose optimization. While we seek benefits, we must also consider and quantify the additional side effects for patients, aiming for the most appropriate dose,” said Shi Hongcheng, Director of Nuclear Medicine at Zhongshan Hospital, Fudan University.

Due to these R&D challenges, the commercialization of radiopharmaceuticals still lags behind some “star products.” For example, in the ADC field, Daiichi Sankyo’s DS-8201 (trastuzumab deruxtecan) achieved global sales of over $4.3 billion in 2025.

Nevertheless, industry experts remain optimistic about the potential of radiopharmaceuticals. Tao Feng, founding partner of Boyuan Capital, believes that the primary goal of drug development is to benefit patients. As long as market potential exists, investment is justified.

Reichen offered an optimistic perspective: the nearly $2 billion annual sales of Pluvicto already surpass many other star drugs targeting important pathways (like KRAS), making it attractive for big pharma.

He also sees unique advantages of radiopharmaceuticals over ADCs in overcoming drug resistance and safety issues. “Pluvicto may not be a blockbuster now, but the future looks promising. The next step for radiopharmaceuticals depends on whether they can achieve better overall survival (OS) data; better data will inevitably lead to better market performance.”

The radiopharmaceutical industry is undoubtedly at a critical turning point from “following” to “innovating.” Although early on, there was unavoidable homogeneous competition around mature targets, this is a necessary phase for emerging sectors to mature.

Currently, more companies are beginning to innovate at the levels of “targets” and “isotopes.” On one hand, they are actively exploring promising new targets like Fibroblast Activation Protein (FAP), even attempting dual-target strategies to overcome tumor heterogeneity; on the other hand, they are moving toward next-generation therapeutic weapons such as alpha-emitting isotopes with greater treatment advantages.

Only by breaking dependence on a single successful pathway, and through source innovation and precision medicine, can radiopharmaceuticals truly usher in a new era of more differentiated, effective, and accessible cancer treatments.

(Science and Technology Innovation Board Daily, Reporter Xu Hong)