In 2026, oncology R&D is being reshaped by:

• Targeted protein degradation (TPD) (PROTACs, molecular glues) tackling historically “undruggable” oncoproteins [1][2][3][4].

• Next-generation precision targets in lung, breast, and hematologic malignancies, often with specific genomic alterations fast‑tracked by regulators [5][6].

• Immune-oncology (I/O) combinations and novel checkpoints, including engineered T cells and NK cells.

Below is a focus on targets (not just drugs), anchored in what is seeing strong clinical progression or regulatory attention in 2025–2026.

Key Target Classes

1. Targeted protein degradation: transcription factors and signaling nodes

TPD is now widely cited by leading cancer centers as one of the most promising approaches in cancer drug discovery for 2026 [1][3][4]. Key targets:

• IKZF1 / IKZF3 (Ikaros family transcription factors)

• Heavily pursued in multiple myeloma and other B‑cell malignancies as molecular-glue degrader targets [2].

• Clinical molecules exploit cereblon-mediated degradation; these proteins remain among the most advanced TPD targets with durable responses in early trials [2][4].

• BTK (Bruton’s tyrosine kinase)

• BTK degraders (e.g., bexobrutideg from Nurix) are being moved into pivotal development aiming to overcome resistance and toxicity seen with covalent BTK inhibitors in CLL and other B‑cell cancers [4].

• Degradation may address resistance driven by BTK mutations and bypass some off‑target effects.

• AURKA (Aurora kinase A) and mutant BRAF

• Degradation of these mitotic and MAPK-pathway regulators is being showcased in 2026 as a way to tackle resistant solid tumors [8].

• Particularly relevant in high‑grade tumors with pathway addiction (e.g., certain colorectal and melanoma subtypes).

• Other emerging TPD targets

• RBM39, GSPT1, CKα1, IKZF2: highlighted in 2026 updates as active clinical molecular glue targets [2].

• The broader trend is that degradation allows targeting regulatory and scaffolding proteins previously considered “undruggable” [3][7].

Implication: TPD targets—especially transcription factors and resistance‑driver kinases—are among the highest‑upside oncology targets in 2026, with multiple candidates transitioning from early phase to pivotal trials.

2. Genomically defined precision targets (especially in lung cancer)

The FDA’s early‑2026 precision oncology update emphasizes specific NSCLC mutations with breakthrough-designated agents [6]:

• EGFR exon 20 insertions, uncommon EGFR mutations, and resistance mutations

• Next‑generation EGFR inhibitors and degraders (e.g., sevabertinib) are advancing for resistance settings [6].

• KRAS G12C and other KRAS alleles

• KRAS G12C remains an important target with ongoing efforts to address resistance; emerging approaches include protein degradation and novel small‑molecule engagement.

• MET exon 14 skipping, RET, NTRK, ALK fusions

• While already drugged, they remain highly promising because of expansion into earlier lines, adjuvant settings, and combinations with I/O and TPD technologies.

Implication: NSCLC continues to be a hotbed of “precision targets,” with regulatory momentum around specific mutations helping de‑risk investment in these pathways.

3. Hormone receptor and HER2‑low / HER2‑mutant targets

• ER (estrogen receptor) and HER2 variants in breast cancer

• Agents such as oral SERDs and ER degraders (e.g., vepdegestrant/ARV‑471 highlighted among promising 2025 drugs [7]) continue to push ER as a high‑value target in both metastatic and adjuvant settings.

• HER2‑low and HER2‑mutant disease have emerged as important target segments, expanding the population benefiting from HER2‑directed ADCs and small molecules.

Implication: ER and HER2 (including low‑expressing and mutant forms) remain among the most commercially and clinically validated targets, with room for better degraders, bispecifics, and ADCs.

4. Immune targets: next‑gen checkpoints and cell-based therapies

While PD‑1/PD‑L1 and CTLA‑4 are now established, 2026 attention focuses on:

• LAG‑3, TIGIT, TIM‑3, and other checkpoints

• Trials at major congresses (ASCO, AACR 2026 previews) highlight these as key combination targets with PD‑1/PD‑L1 inhibitors, particularly in “cold” tumors and relapse settings [2][5][8].

• CAR‑T and other engineered cell targets

• New CAR‑T constructs against BCMA, CD19, and dual‑antigen or armored CARs show expanding indications beyond hematologic cancers [1][5].

• Solid‑tumor CAR‑T and allogeneic cell therapies (including invariant NKT‑cell therapies like AgenT‑797 listed among promising candidates [7]) indicate growing target exploration in mesothelin, Claudin‑6, and other antigens.

Implication: The most promising I/O targets are not single antigens but combinatorial checkpoint constellations and multi‑antigen cell targets designed to overcome resistance and immune evasion.

5. DNA damage response (DDR) and synthetic lethality

Although not fully new, DDR targets remain central:

• PARP (broadened indications and combinations), ATR, ATM, CHK1/2, and related repair proteins.

• Efforts to pair DDR inhibitors with TPD or I/O are gaining traction, particularly in BRCA‑mutated, HRD+ and other repair‑deficient tumors.

Implication: DDR targets are now part of a combinatorial backbone; their promise lies increasingly in rational combinations rather than monotherapy.

Counterarguments & Uncertainties

• Several TPD programs have encountered toxicity and PK challenges, so not all TPD targets will translate into approved drugs.

• Regulatory guidance around first‑in‑class degraders and complex I/O combinations is evolving, potentially slowing development timelines.

• Many apparently “promising” targets from 2020–2024 underperformed in phase III; the same risk applies to 2026 targets.

Overall Implications for 2026

• Highest-risk/highest-reward: TPD targets (IKZF1/3, BTK, AURKA, mutant BRAF, RBM39, GSPT1).

• High-probability near‑term impact: genomically defined NSCLC targets (EGFR, MET, KRAS, RET, NTRK) and ER/HER2 variants.

• Platform-level bets: multi‑checkpoint I/O, next‑gen CAR‑T/NK, and DDR combinations.