Moderna Surges on Cancer Vaccine, Marvell Gains on Google Deal as US-Iran Tensions Persist

US markets absorbed several significant company and geopolitical developments this week, with Moderna (MRNA) shares surging after positive late-stage data for its personalised cancer vaccine developed with Merck, while Marvell Technology (MRVL) gained following a new custom-chip agreement with Google. At the same time, escalating economic pressure on Iran and uncertainty surrounding the Strait of Hormuz continued to put global oil markets in focus. 

Here are the latest updates:

TL;DR

• Moderna (MRNA) surged after its personalised mRNA cancer vaccine with Merck met key endpoints in a Phase 3 melanoma trial.

• Marvell Technology (MRVL) jumped following an expanded custom AI chip agreement with Google, which also received warrants to potentially acquire nearly 59 million Marvell shares.

• US-Iran tensions remained elevated as Washington announced additional economic pressure on Tehran while diplomatic negotiations remained stalled.

• The Strait of Hormuz stayed in focus, with continued shipping restrictions keeping global oil supplies and energy markets under scrutiny.

Key Developments

Why Did Moderna Stock Surge?

Moderna shares surged on Wednesday, 19 August, after the biotechnology company and Merck reported positive interim results from a Phase 3 trial of intismeran, Moderna's personalised mRNA cancer therapy, in patients with high-risk melanoma. Moderna stock price jumped about 90% in pre-market trading following the announcement, while the stock subsequently extended its gains during the session. 

The treatment combines intismeran with Merck's immunotherapy drug Keytruda. In a trial involving 1,137 patients whose melanoma had been surgically removed, the combination met its primary objective of improving recurrence-free survival and also achieved its secondary goal related to preventing the cancer from spreading to other parts of the body. The companies said no new safety signals had emerged and plan to present detailed results at a medical meeting and discuss the findings with regulators. 

The results are particularly significant for Moderna because they represent the first positive late-stage trial result for an mRNA-based personalised cancer vaccine. The company has been seeking to broaden its product portfolio beyond COVID-19 vaccines, and the melanoma programme is one of its most closely watched oncology assets. 

Marvell Rises on Expanded Google AI Chip Partnership

Marvell Technology shares also moved sharply higher on Wednesday after the semiconductor company announced an agreement to develop custom chips for Alphabet's Google. The agreement expands Marvell's exposure to the rapidly growing market for specialised artificial-intelligence infrastructure, including technologies used alongside Google's Tensor Processing Units, or TPUs.  

As part of the arrangement, Marvell issued Google a warrant giving it the right to acquire nearly 59 million Marvell shares at $206.58 per share, representing a potential stake worth roughly $12.2 billion at the exercise price. Marvell said its work for Google would cover technologies including AI inference accelerators, storage, networking and memory-interface controllers. Marvell shares jumped by double digits in pre-market trading following the announcement, while rival Broadcom initially moved lower. 

The agreement follows earlier reports that Google was considering working with Marvell on additional custom silicon as large technology companies increase spending on proprietary AI processors. Google already uses TPUs for AI training and inference, while companies across the sector have been seeking additional computing capacity and alternatives to conventional graphics processors. The development therefore adds another company-specific catalyst within the semiconductor sector and the wider NASDAQ technology complex. 

Latest US-Iran Developments Keep Hormuz in Focus

Geopolitical risk remained another important market factor. On Wednesday, US President Donald Trump announced what he described as a new economic operation against Iran, saying Washington would pursue economic isolation and warning that countries or institutions providing Iran with financial support could face US economic consequences. The announcement specifically referenced oil smuggling, financial transfers, exchange houses, ship registries and front companies. 

The announcement came as diplomatic negotiations remained stalled. Trump said earlier that there were no US-Iran talks currently underway or scheduled, while Iranian officials have maintained that the Strait of Hormuz will not fully reopen unless Washington meets conditions including lifting its blockade and oil sanctions and releasing frozen Iranian assets. The June memorandum between the two countries had unravelled over disputes concerning control of the strategically important waterway. 

The US blockade also remains in force. According to CBS News, US Central Command said 65 vessels had been prevented from entering or leaving Iranian ports since the blockade was restarted on 14 July. Only 10 commercial vessels were confirmed to have transited the Strait of Hormuz on Tuesday, 18 August, highlighting the continued disruption to a route that carried a substantial share of global oil trade before the conflict. (Source: CBS News)

Why the Strait of Hormuz Remains Important for Markets

The continuing dispute over the Strait of Hormuz has implications beyond the Middle East because the waterway is one of the world's most important energy corridors. Restrictions on tanker traffic can affect crude and liquefied natural gas supplies, shipping costs and ultimately global energy prices. Confirmed crossings had fallen sharply compared with pre-conflict levels, contributing to continued volatility in crude markets. 

The latest developments therefore leave markets monitoring two distinct sets of catalysts: company-specific news in biotechnology and artificial intelligence, where Moderna and Marvell experienced substantial share-price moves, and geopolitical developments that continue to affect oil prices and broader market sentiment. The next developments in Moderna's regulatory process, Google's expanded relationship with Marvell and US-Iran negotiations may remain closely watched by market participants. 

*Past performance does not guarantee future results. The above is for marketing and general informational purposes only, and these are only projections and should not be taken as investment research, investment advice or a personal recommendation.